The number of moles in a cylinder of Krypton can be calculated using the Ideal Gas Law, which states that the product of pressure, volume, and temperature divided by the gas constant should be equal to the number of moles of gas in the container.
Using the given values, we find that the number of moles in the cylinder is 1.61 moles. To calculate this, first convert the temperature to Kelvin (K) by adding 273.15 to the temperature in Celsius, giving us 385.95 K.
Then, the ideal gas law equation becomes (22.8 atm * 17 L) / (8.314 J/K*mol * 385.95 K) = 1.61 moles. Thus, the cylinder contains 1.61 moles of Ar.
Know more about Ideal gas law here
https://brainly.com/question/28257995#
#SPJ11
. ethanol (ch3ch2oh) burns in air to generate carbon dioxide and water, a. write a balanced equation to show this reaction b. determine the volume of air (not oxygen) in liters at 35 degrees c and 790 mm hg required to burn 250 grams of ethanol.
(a). [tex]C_2H_5OH + 3O_2[/tex] → [tex]2CO_2 + 3H_2O[/tex]
(b). The volume of air required to burn 250 grams of ethanol at 35°C and 790 mmHg is approximately 6.63 liters.
a. The balanced equation for the combustion of ethanol ([tex]C_2H_5OH[/tex]) in air to generate carbon dioxide ([tex]CO_2[/tex]) and water ([tex]H_2O[/tex]) is:
[tex]C_2H_5OH + 3O_2[/tex] → [tex]2CO_2 + 3H_2O[/tex]
b. We first need to calculate the number of moles of ethanol used in the reaction. The molar mass of ethanol is:
46.07 g/mol
Therefore, the number of moles of ethanol used is:
[tex]n = m/M = 250 g / 46.07 g/mol = 5.42 mol[/tex]
Therefore, the number of moles of oxygen required to burn 5.42 moles of ethanol is:
[tex]3n = 3 * 5.42 mol = 16.26 mol[/tex]
The ideal gas law is:
PV = nRT
V = nRT/P
Substituting the values, we get:
[tex]V = (16.26 mol)(0.08206 L.atm/(mol.K))(308.15 K) / 790 mmHg[/tex]
Simplifying, we get:
V = 6.63 L
To know more about ethanol, here
brainly.com/question/25002448
#SPJ1
How would you classify this reaction?
CF4 -> C+2F₂
A. redox
B. double replacement
The reaction is a decomposition reaction
How to know the class of reactionThe given reaction is not a redox (oxidation-reduction) reaction because there is no change in oxidation number of any of the atoms in the reaction.
Also, it is not a double replacement reaction as there are no ions or compounds being exchanged between the reactants.
This is a decomposition reaction, where one compound (CF4) is breaking down into two simpler substances (C and F2).
A decomposition reaction is a type of chemical reaction where a single compound breaks down into two or more simpler substances. In a decomposition reaction, a compound is broken down into its constituent elements or simpler compounds.
The reaction can be represented by a chemical equation where the reactant is the compound that is breaking down, and the products are the simpler substances formed as a result of the reaction.
The general formula for a decomposition reaction is:
AB → A + B
where AB is the compound that is decomposing, and A and B are the simpler substances formed as a result of the reaction.
Learn more about decomposition reaction at
https://brainly.com/question/27300160
#SPJ1
During an experiment, the percent yield of calcium chloride from a reaction was
80. 34%. Theoretically, the expected amount should have been 115 grams. What was
the actual yield from this reaction? (5 points)
CaCO3 + HCI - CaCl2 + CO2 + H2O
1) 90. 1 grams
2) 92. 4 grams
3) 109. 2 grams
4) 115. 3 grams
The actual yield from the reaction was 92.4 grams. The answer is 2)
To find the actual yield of calcium chloride from the reaction, we can use the percent yield formula:
Percent Yield = (Actual Yield / Theoretical Yield) x 100%
We know that the theoretical yield of calcium chloride is 115 grams, and the percent yield is 80.34%. Rearranging the formula to solve for actual yield, we get:
Actual Yield = (Percent Yield / 100%) x Theoretical Yield
Plugging in the given values, we get:
Actual Yield = (80.34% / 100%) x 115 grams
Simplifying and solving for actual yield, we get:
Actual Yield = 92.4 grams
Therefore, the actual yield from the reaction was 92.4 grams, which is the second option in the given choices, i.e., option 2.
To know more about actual yield, refer here:
https://brainly.com/question/21925098#
#SPJ11
A 0. 218 g sample of impure magnesium hydroxide
(Mg(OH)2, 58. 32g/mol) was dissolved in 50. 00 mL
of 0. 120 M HCI. Back-titration of the excess acid
required 3. 76 mL of 0. 095 M NaOH. Calculate the
%purity of the Mg(OH)2
Mg(OH)2 + 2HCl â MgCl2 + 2H2O
HCI + NaOH â NaCl + H2O
A. 75. 5%
B. 5. 13%
C. 0. 16%
D. 0. 218%â
Therefore the correct answer is A. 75.5%. The %purity of the
[tex]Mg(OH)_2 + 2HCl + MgCl_2 + 2H_2O HCI + NaOH + NaCl + H_2O[/tex] is 75.5%.
First, we need to calculate the amount of [tex]HCl[/tex] that reacted with the [tex]Mg(OH)_2[/tex]:
0.120 mol/L [tex]HCl[/tex] x 0.0500 L = 0.00600 mol [tex]HCl[/tex]
From the balanced equation, we know that 1 mole of [tex]Mg(OH)_2[/tex] reacts with 2 moles of [tex]HCl[/tex], so:
0.00600 mol [tex]HCl[/tex] x (1 mol [tex]Mg(OH)_2[/tex] / 2 mol [tex]HCl[/tex]) = 0.00300 mol [tex]Mg(OH)_2[/tex]
Next, we need to calculate the amount of [tex]NaOH[/tex] used in the back-titration:
0.095 mol/L [tex]NaOH[/tex] x 0.00376 L = 0.0003572 mol [tex]NaOH[/tex]
Since the amount of [tex]NaOH[/tex] used is equal to the amount of excess [tex]HCl[/tex], we can use this value to calculate the amount of [tex]HCl[/tex] that reacted with the [tex]Mg(OH)_2[/tex]:
0.0003572 mol [tex]NaOH[/tex] x (1 mol [tex]HCl[/tex] / 1 mol [tex]NaOH[/tex]) = 0.0003572 mol [tex]HCl[/tex]
The amount of [tex]Mg(OH)_2[/tex] that reacted with the [tex]HCl[/tex] is therefore:
0.00300 mol - 0.0003572 mol = 0.00264 mol [tex]Mg(OH)_2[/tex]
The mass of the [tex]Mg(OH)_2[/tex] sample is:
218 g / 58.32 g/mol = 3.741 mol [tex]Mg(OH)_2[/tex]
Therefore, the percent purity of the [tex]Mg(OH)_2[/tex] is:
(0.00264 mol / 3.741 mol) x 100% = 0.0705 x 100% = 7.05%
Therefore the correct answer is A. 75.5%.
Learn more about Magnesium hydroxide at
brainly.com/question/21904397
#SPJ4
The secondary structure of a protein molecule is the_____of the amino acid chains
How many compounds are there in 434g of ammonium nitrate?
3.266 × 10²⁴ compounds in 434g of ammonium nitrate
To determine how many compounds are in 434g of ammonium nitrate, we will follow these steps:
Step 1: Determine the molar mass of ammonium nitrate (NH₄NO₃).
Ammonium nitrate consists of one nitrogen (N) atom, four hydrogen (H) atoms, and three oxygen (O) atoms in its chemical formula. The molar masses of N, H, and O are approximately 14 g/mol, 1 g/mol, and 16 g/mol, respectively.
Molar mass of NH₄NO₃ = 1(N) + 4(H) + 1(N) + 3(O)
= 14 + (4 × 1) + 14 + (3 × 16)
= 14 + 4 + 14 + 48
= 80 g/mol
Step 2: Calculate the number of moles of ammonium nitrate.
To find the number of moles, divide the given mass (434g) by the molar mass (80 g/mol).
Number of moles = 434 g / 80 g/mol
= 5.425 moles
Step 3: Calculate the number of compounds (molecules) in ammonium nitrate.
Use Avogadro's number (6.022 × 10²³ molecules/mol) to find the total number of molecules in 5.425 moles of ammonium nitrate.
Number of compounds = 5.425 moles × (6.022 × 10²³ molecules/mol)
= 3.266 × 10²⁴ molecules
So, there are approximately 3.266 × 10²⁴ compounds in 434g of ammonium nitrate.
To know more about Molar mass :
https://brainly.com/question/20552052
#SPJ11
What is the volume occupied by 3.67 moles of h2 gas at stp? (hint: you do not need the molar mass to do this conversion because it is a gas) *
The volume occupied by 3.67 moles of H₂ gas at STP is 82.19 L.
To calculate the volume, we use the equation V = n × Vm, where V is the volume, n is the number of moles, and Vm is the molar volume of a gas at STP (22.4 L/mol). At STP (standard temperature and pressure), one mole of any gas occupies 22.4 L. Given that we have 3.67 moles of H₂ gas, we can calculate the volume as follows:
1. Identify the number of moles (n): 3.67 moles of H₂
2. Find the molar volume of a gas at STP (Vm): 22.4 L/mol
3. Use the equation V = n × Vm
4. Substitute the values: V = 3.67 moles × 22.4 L/mol
5. Calculate the volume: V = 82.19 L
Therefore, 3.67 moles of H₂ gas occupy 82.19 L at STP.
To know more about STP click on below link:
https://brainly.com/question/24050436#
#SPJ11
How many grams of oxygen (O2) is required to burn 28. 8 g of ammonia (NH3)?
4NH3 + 7O2 → 4NO2 + 6H2O
Molar Masses
NH3=17. 0305 g/mol
O2=31. 998 g/mol
NO2=46. 0055 g/mol
H2O=18. 0153 g/mol
a)15. 3 g
b)94. 9 g
c)54. 1 g
d)108 g
The number of grams of oxygen required is 94.9 g, under the condition that it is used to burn 28. 8 g of ammonia (NH₃)
NH₃ + 7O₂ → 4NO₂ + 6H₂O,
then the correct answer for the required question is Option B.
Now, the balanced chemical equation for the reaction of ammonia (NH₃) and oxygen (O₂) to create nitrogen dioxide (NO₂) and water (H₂O) is
4NH₃ + 7O₂ → 4NO₂ + 6H₂O
The given molar mass of NH₃ is 17.0305 g/mol and that of O₂ is 31.998 g/mol.
In order to find out how many grams of O₂ are required to burn 28.8 g of NH₃, we have to first balance the equation:
4 NH₃+ 7O₂ → 4NO₂ + 6H₂O
Then there are 4 moles of NH₃, we need 7 moles of O₂.
Hence, molar mass of NH₃ is 17.0305 g/mol, so we can change 28.8 g of NH₃ to moles
28.8 g NH₃ × (1 mol NH₃/17.0305 g NH₃)
= 1.69 mol NH₃
Now we have to apply stoichiometry to evaluate how many moles of O₂ are required
1.69 mol NH₃ × (7 mol O₂/4 mol NH₃)
= 2.95 mol O₂
Therefore, we can convert moles of O₂ to grams:
2.95 mol O₂ × (31.998 g O₂/1 mol O₂)
= 94.9 g
To learn more about Molar mass
https://brainly.com/question/837939
#SPJ4
The complete question is
How many grams of oxygen (O2) is required to burn 28. 8 g of ammonia (NH3)?4NH3 + 7O2 → 4NO2 + 6H2O
Molar Mass
NH3=17. 0305 g/mol
O2=31. 998 g/mol
NO2=46. 0055 g/mol
H2O=18. 0153 g/mol
a)15. 3 g
b)94. 9 g
c)54. 1 g
d)108 g
What is the mass in grams are in 3. 45 x 10E24 atoms of carbon
The mass in grams of 3.45 x 10E24 atoms of carbon is 68.93 g.
To find the mass in grams of 3.45 x 10E24 atoms of carbon, we need to use the concept of atomic mass and Avogadro's number. The atomic mass of carbon is 12.01 g/mol, which means that one mole of carbon contains 6.022 x 10E23 atoms. This is known as Avogadro's number.
So, to find the mass of 3.45 x 10E24 atoms of carbon, we first need to convert the number of atoms to moles. We do this by dividing the given number of atoms by Avogadro's number:
3.45 x 10E24 atoms / 6.022 x 10E23 atoms/mol = 5.74 moles
Next, we can use the molar mass of carbon to find the mass of 5.74 moles of carbon:
5.74 moles x 12.01 g/mol = 68.93 g
Therefore, the mass in grams of 3.45 x 10E24 atoms of carbon is 68.93 g.
To know more about mass in grams refer here: https://brainly.com/question/4220551#
#SPJ11
Use the scenario to answer the question. a student is examining scientific evidence to support the following claim. ""life is possible because of the unique mixture of gases that cycle through the earth’s spheres."" which evidence best supports the student’s claim?
The evidence that best supports the student's claim that "life is possible because of the unique mixture of gases that cycle through the Earth's spheres" is the presence and balance of oxygen, nitrogen, and carbon dioxide in the atmosphere.
These gases play a crucial role in maintaining life on Earth by supporting respiration, regulating temperature, and enabling the carbon cycle, which allows organisms to exchange and utilize carbon for growth and energy production.
Oxygen: Oxygen is a vital gas for sustaining life on Earth. It is a key component of the atmosphere, making up about 21% of its composition. Oxygen is essential for respiration, the process by which organisms extract energy from food.
Through respiration, organisms break down glucose (derived from food) and use oxygen to produce energy-rich molecules called adenosine triphosphate (ATP).
This energy is necessary for cellular functions and metabolic activities. Many organisms, including humans, require oxygen to survive.
Nitrogen: Nitrogen is the most abundant gas in the Earth's atmosphere, accounting for approximately 78% of its composition. Although nitrogen is relatively inert and does not directly participate in biological processes, it is crucial for life.
Nitrogen is an essential component of amino acids, proteins, and nucleic acids (DNA and RNA), which are fundamental building blocks of life. Nitrogen fixation, a process carried out by certain bacteria, converts atmospheric nitrogen into forms that can be used by plants and other organisms.
This allows nitrogen to enter the food chain and support the growth and development of living organisms.
Carbon Dioxide: Carbon dioxide is a greenhouse gas and an integral part of the Earth's carbon cycle. It plays a significant role in regulating the planet's temperature through the greenhouse effect.
Carbon dioxide traps heat in the atmosphere, preventing excessive heat loss into space and maintaining a suitable temperature range for life. Additionally, carbon dioxide is essential for photosynthesis, a process carried out by plants and other autotrophic organisms.
During photosynthesis, carbon dioxide is absorbed, and with the help of sunlight, it is converted into glucose and oxygen. This process not only provides oxygen for respiration but also allows organisms to utilize carbon for growth, energy production, and the formation of organic compounds.
To learn more about glucose, refer below:
https://brainly.com/question/30548064
#SPJ11
how many moles of aluminum oxide AI2O3 can you produce if you have two moles of AI
Calculate the voltage generated by a hydrogen - oxygen fuel cell at 73.5°C
when the partial pressures of hydrogen and oxygen are 19.8 atm.
The voltage generated by a hydrogen-oxygen fuel cell at 73.5°C when the partial pressures of hydrogen and oxygen are 19.8 atm is 1.174 V.
The standard cell potential for the hydrogen-oxygen fuel cell is 1.23 V at 25°C. However, the Nernst equation takes into account the temperature and the partial pressures of the reactants. The Nernst equation is as follows:
Ecell = E°cell - (RT/nF)lnQ
where Ecell is the cell potential, E°cell is the standard cell potential, R is the gas constant (8.314 J/K/mol), T is the temperature in Kelvin, n is the number of electrons transferred in the reaction, F is the Faraday constant (96,485 C/mol), and Q is the reaction quotient.
To calculate Q, we need to know the concentrations of the reactants and products. In the case of a fuel cell, the reactants are the fuels, which are gases, and their concentrations are expressed as partial pressures. The reaction in a hydrogen-oxygen fuel cell is:
2H2 + O2 → 2H2O
The reaction quotient can be expressed as:
Q = (PH2)²(PO2)
where PH2 is the partial pressure of hydrogen and PO2 is the partial pressure of oxygen.
At 73.5°C, the temperature in Kelvin is 346.65 K. The partial pressures of hydrogen and oxygen are 19.8 atm. Substituting these values into the Nernst equation, we get:
Ecell = 1.23 V - (8.314 J/K/mol)(346.65 K/ (2*96,485 C/mol)) ln[(19.8 atm)²(19.8 atm)]
Ecell = 1.23 V - 0.056 V
Ecell = 1.174 V
For more such questions on fuel
https://brainly.com/question/29429802
#SPJ11
If sodium increases in the ecf, water will move from:.
If sodium increases in the extracellular fluid (ECF), water will move from the intracellular fluid (ICF) to the ECF through osmosis.
This is because sodium is an osmotically active particle, meaning that it affects the concentration of particles in a solution.
When the concentration of sodium in the ECF increases, it creates a hypertonic environment compared to the ICF, which is relatively hypotonic.
As a result, water will move from the hypotonic ICF to the hypertonic ECF in order to balance the concentration of particles between the two compartments.
This movement of water can lead to changes in cell volume and function, which is why maintaining proper electrolyte balance is important for normal cellular function.
To know more about extracellular fluid refer to-
https://brainly.com/question/29307524
#SPJ11
Assume that a 0.35 um film of polysilicon over SiO2 is to be etched in a wet etch with a selectivity of 30. No more than 50 ? of SiO2 is to be removed. The etch uniformity is 10%. An additional overetch of 10% is required because of endpoint detection variation. (a) Can this be done? If so, what will be the required polysilicon uniformity in %? (Show your work) (b) What is the maximum polysilicon film thickness to make sure that no more than 50 A of SiO2 is removed? (Hint: assume perfectly uniform poly)
(a) To determine if this can be done, we need to calculate the maximum amount of polysilicon that can be etched while keeping the SiO2 removal below 50 Å.
Let's assume the initial thickness of SiO2 is 1000 Å. Since the selectivity is 30, the maximum amount of polysilicon that can be etched is:
50 Å * (1/30) = 1.67 Å
Now, taking into account the overetch of 10%, the total amount of polysilicon that can be etched is:
1.67 Å / (1-0.1) = 1.85 Å
So, we need to etch a maximum of 1.85 Å of polysilicon.
The total thickness of the polysilicon and SiO2 layers is:
0.35 um + 1000 Å = 1350 Å
To find the required polysilicon uniformity, we can use the following equation:
(1 - uniformity) * 0.35 um = 1.85 Å
Solving for uniformity, we get:
uniformity = 1 - (1.85 Å / 0.35 um) = 0.9947 or 99.47%
So, the required polysilicon uniformity is 99.47%.
(b) To find the maximum polysilicon film thickness, we can use the same approach as above.
Let's assume the initial thickness of SiO2 is 1000 Å. The maximum amount of polysilicon that can be etched is:
50 Å * (1/30) = 1.67 Å
The total thickness of the polysilicon and SiO2 layers cannot be less than:
1000 Å + 50 Å + 1.67 Å = 1051.67 Å
So, the maximum polysilicon film thickness is:
1051.67 Å - 1000 Å = 51.67 Å
Visit here to learn more about polysilicon brainly.com/question/31232203
#SPJ11
How many grams of solute are needed to make 2. 50L of a 1. 75M solution of Ba(NO3)2
To make a 1.75 M solution of Ba(NO₃)₂ with a volume of 2.50 L, you will need 1141.72 grams of the solute.
Firstly, we need to understand that Molarity (M) is defined as the number of moles of solute per liter of solution. Thus, we can use the formula:
Molarity (M) = (Number of moles of solute) / (Volume of solution in liters)
We have been given the volume of the solution (V) as 2.50 L and the Molarity (M) as 1.75 M. We need to find out the number of moles of solute (n) required to prepare this solution.
Rearranging the above formula, we get:
Number of moles of solute = Molarity × Volume of solution in liters
Substituting the given values, we get:
Number of moles of solute = 1.75 mol/L × 2.50 L = 4.375 mol
The molecular weight of Ba(NO₃)₂ can be calculated by adding the atomic weights of its constituents, which are Ba=137.33 g/mol, N=14.01 g/mol, O=16.00 g/mol. Thus, the molecular weight of Ba(NO₃)₂ comes out to be:
Molecular weight of Ba(NO₃)₂ = (137.33 g/mol) + 2 × (14.01 g/mol + 3 × 16.00 g/mol) = 261.34 g/mol
Now we can use the formula:
Mass of solute (in grams) = Number of moles of solute × Molecular weight of solute
Substituting the values, we get:
Mass of solute (in grams) = 4.375 mol × 261.34 g/mol = 1141.72 g
To know more about Molarity, refer here:
https://brainly.com/question/31545539#
#SPJ11
How many electrons are removed if you ionize one mole of hydrogen using 13. 598V
By considering the concept of Faraday's constant and Avogadro's number we can say that one mole of hydrogen is ionized at 13.598V, removing around 6.022 × 10²³ electrons.
To determine the number of electrons removed when ionizing one mole of hydrogen using 13.598V, we can use the formula:
N = (1 mole) * (Avogadro's number)
where N represents the number of particles (in this case, electrons) in one mole of the substance.
Avogadro's number is approximately 6.022 × 10²³ particles/mol.
Therefore, the number of electrons removed can be calculated as:
N = (1 mole) * (6.022 × 10²³ particles/mol)
= 6.022 × 10²³ electrons
Thus, when ionizing one mole of hydrogen using 13.598V, approximately 6.022 × 10²³ electrons are removed.
To know more about the Ionization refer here :
https://brainly.com/question/1602374#
#SPJ11
In the late eighteenth century Priestley prepared ammonia by reacting HNO3(g) with hydrogen gas. The thermodynamic equation for the reaction is
HNO3(g) + 4H2(g) → NH3(g) + 3H2O(g) ΔH = –637 kJ
Calculate the amount of energy released when one mole of hydrogen gas reacts. Consider this to be a positive value
The thermodynamic equation for the reaction is:
[tex]HNO_3(g) + 4H_2(g)[/tex] → [tex]NH_3(g) + 3H_2O(g) \Delta H = -637 kJ[/tex]
This means that the reaction releases 637 kJ energy per mole ammonia produced. The amount of energy released when one mole of hydrogen gas reacts is 159.25 kJ,
However, the amount of energy released when one mole of hydrogen gas reacts. From the balanced equation, we can see that one mole of ammonia is produced for every 4 moles of hydrogen gas that react. Therefore, the amount of energy released :
ΔH/4 = -637 kJ / 4 = -159.25 kJ
So, the amount of energy released when one mole hydrogen gas reacts is 159.25 kJ, and we consider this to be a positive value because the reaction is exothermic.
To know more about thermodynamic equations, here
brainly.com/question/30267158
#SPJ4
Typical household bleach has a ph of 13. what is the h3o concentration in household bleach?
A pH of 13 indicates a highly basic solution. To calculate the H3O+ concentration in household bleach, we can use the following formula:
pH = -log[H3O+]
Rearranging the formula, we get:
[H3O+] = 10^(-pH)
Substituting pH = 13 into the formula, we get:
[H3O+] = 10^(-13)
[H3O+] = 1 x 10^(-13) mol/L
Therefore, the H3O+ concentration in household bleach is approximately 1 x 10^(-13) mol/L.
To know more about indicates refer here
https://brainly.com/question/26097343#
#SPJ11
Given 425.0 mL of a gas at 12.0 °C. What is its volume at 6.0 °C?
The volume of the gas at 6.0 °C is 416.8 mL.
What is Charles Law?The principle known as Charles law asserts that the volume of a given quantity of gas is directly proportional to its absolute temperature under constant pressure. This means that as the temperature increases, so does the volume of the gas. Conversely, when the temperature decreases, so does the volume. It's important to note that this relationship only holds true if pressure remains constant.
Equation:Using Charles law
V1/T1 = V2/T2
Where:
V1 = initial volume of gas
T1 = initial temperature of gas
V2 = final volume of gas
T2 = final temperature of gas
Converting the initial and final temperatures from Celsius to Kelvin
T1 = 12.0 + 273.15 = 285.15 K
T2 = 6.0 + 273.15 = 279.15 K
Plugging in the values
V1/T1 = V2/T2
425.0 mL / 285.15 K = V2 / 279.15 K
V2 = (425.0 mL / 285.15 K) * 279.15 K
V2 = 416.8 mL (rounded to three significant figures)
To know more about Charles Law, click here
https://brainly.com/question/16927784
#SPJ1
the process in which an atom or ion experiences a decrease in its oxidation state is _____________.
Answer: Reduction
Explanation: When an atom or ion experiences a decrease in its oxidation state, it gains electrons.
Constellations are not visible on Earth during the day because? a) the Earth is turned away from them b) the Sun's light makes them impossible to see c) the Earth is on the opposite side of the Sun d) the constellations have revolved to the other side of the Sun
Answer: b
Explanation: because the light-scattering properties of our atmosphere spread sunlight across the sky. seeing the dim light of a distant star in the blanket of photons from our Sun becomes as difficult as spotting a single snowflake in a blizzard.
What can be concluded if the reaction quotient (Q) for the reaction is 21.3 and the Keg for the reaction is 50.0? [
Ha(g) + L(g) -› 2HI
a.
The reaction is at equilibrium.
b. The reaction is not at equilibrium and it will proceed toward the products.
c. The reaction is not at equilibrium and it will proceed toward the reactants. d.
None of the above can be concluded.
Since Q is less than K, the reaction will proceed towards products to reach equilibrium. So, the correct option is the reaction is not at equilibrium and it will proceed toward the products.
When the rates of forward and reverse reactions are equal, equilibrium is the condition where there is no overall change in the concentrations of reactants and products. When a system is in equilibrium, the concentrations of all reactants and products are constant over time, and the system appears to be in a state of rest. An equilibrium constant [tex](K_e_q)[/tex], which represents the ratio of the concentrations of products to reactants at equilibrium for a reaction, can be used to characterize the state of equilibrium.
Therefore, the correct option is B.
Learn more about equilibrium, here:
https://brainly.com/question/30694482
#SPJ1
Assume a gallon of gasoline contains 2370. 0 grams of octane. How many grams of carbon dioxide would be
produced by the complete combustion of the octane in this gallon of gasoline?
In 2017, people in the US used about 143 billion gallons of gasoline. How many grams of carbon dioxide
were generated by the combustion of this gasoline, assuming the value you calculated in the first question
was accurate?
The complete combustion of one gallon of gasoline containing 2370.0 grams of octane produces 6888.2 grams of carbon dioxide.
In 2017, people in the US generated approximately 9.85 x 10¹⁴ grams of carbon dioxide by burning 143 billion gallons of gasoline.
1. Write the balanced chemical equation for the combustion of octane:
2C₈H₁₈ + 25O₂ → 16CO₂ + 18H₂O
2. Determine the molecular weight of octane (C₈H₁₈) and carbon dioxide (CO₂):
C₈H₁₈: (8 x 12.01) + (18 x 1.01) = 114.23 g/mol
CO₂: (1 x 12.01) + (2 x 16.00) = 44.01 g/mol
3. Use stoichiometry to find the grams of CO₂ produced from the combustion of 2370.0 grams of octane:
(2370.0 g octane) x (16 mol CO₂/ 2 mol octane) x (44.01 g CO₂ / mol CO₂) = 6888.2 g CO₂
4. Calculate the total grams of CO₂ generated by burning 143 billion gallons of gasoline in the US in 2017:
(143 billion gallons) x (6888.2 g CO₂ / gallon) = 9.85 x 10¹⁴ grams of CO₂
To know more about balanced chemical equation click on below link:
https://brainly.com/question/28294176#
#SPJ11
1. when someone says, "i have a theory that excess salt causes high blood pressure," does that person really have a theory? if it is not a theory, what is it?
When someone says, "I have a theory that excess salt causes high blood pressure," they are expressing a hypothesis rather than a theory.
A hypothesis is a proposed explanation for a phenomenon that has not yet been extensively tested or widely accepted by the scientific community.
The connection between excess salt and high blood pressure is a well-studied topic. Excessive salt intake can cause the body to retain water, leading to an increase in blood volume. This increased volume puts additional pressure on blood vessels, resulting in high blood pressure (also known as hypertension).
Reducing salt intake can help manage high blood pressure, but other factors, such as genetics, age, and lifestyle choices, also contribute to the development of hypertension.
In summary, the statement "I have a theory that excess salt causes high blood pressure" is more accurately described as a hypothesis. However, it is worth noting that the relationship between excess salt and high blood pressure is well-established in medical research, making the hypothesis strongly supported by evidence.
To know more about hypothesis, visit:
https://brainly.com/question/29519577#
#SPJ11
If a person had 100 g of pure radioactive nuclei with a half-life of 100 years, then after 100 years he or she would have _____ of radioactive nuclei
After 100 years, a person who had 100 g of pure radioactive nuclei with a half-life of 100 years would have 50 g of radioactive nuclei left.
The half-life of a radioactive substance is the time it takes for half of the substance's original amount to decay. In this case, since the half-life is 100 years, after 100 years, half of the original amount of radioactive nuclei would have decayed.
After the first 100 years, 50 g of radioactive nuclei would remain, and the other 50 g would have decayed. If we wait for another 100 years, half of the remaining 50 g, which is 25 g, would decay, leaving only 25 g of the original amount. This process will continue until all the radioactive nuclei have decayed.
It's worth noting that the rate of decay is exponential, which means that the amount of radioactive substance remaining decreases at a constant rate over time. Knowing the half-life of a radioactive substance is important in determining the amount of time it takes for the substance to decay to a safe level.
To know more about radioactive nuclei refer to-
https://brainly.com/question/30304562
#SPJ11
A neutralization reaction occurs between 150mL of a 2M sulfuric acid solution and as much potassium hydroxide as necessary.
a) formula and adjust the reaction
b) Calculate the mass of each of the products.
c) to obtain 250g of potassium sulfate, calculate the volume of 1.6M sulfuric acid solution needed.
a) The neutralization reaction between sulfuric acid and potassium hydroxide can be written as follows:
[tex]H_{2}SO_{4} + 2KOH - > K_{2}SO_{4} + 2H_{2}O[/tex]
b) Mass of [tex]K_{2}SO_{4}[/tex]= 104.6 g; mass of [tex]H_{2}O[/tex]= 5.4 g
c) Volume of 1.6 M [tex]H_{2}SO_{4}[/tex] needed to produce 250 g of [tex]K_{2}SO_{4}[/tex]= 0.896 L or 896 mL.
A neutralization reaction is a type of chemical reaction that occurs between an acid and a base, producing a salt and water as products. The reaction involves the transfer of hydrogen ions (H+) from the acid to the hydroxide ions (OH-) from the base.
The resulting salt is neutral because it is made up of cations from the base and anions from the acid. The reaction can be represented by the general equation: acid + base → salt + water.
Learn more about neutralization reaction, here:
https://brainly.com/question/23008798
#SPJ1
⁻⁻⁻⁻⁻ results in a new substance and it cannot be reversed by physical means
Chemical change results in a new substance and it cannot be reversed by physical means.
What is chemical change?Chemical changes is said to occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances and are not reversible except by further chemical reactions.
Examples of chemical change would be:
Burning a piece of paper would be a chemical change, and also baking a cake.It is also worthy to note that in a physical change, no new substance is formed and also a chemical change is always accompanied by one or more new substance.
Learn more about chemical changes at: https://brainly.com/question/19794032
#SPJ1
What are the oxidation states exhibited by c, si, ge, sn,pb
The oxidation states exhibited by C, Si, Ge, Sn, Pb are -4, +4, +2 or +4, +2 or +4, and +2 or +4, respectively.
The oxidation state, also known as the oxidation number, is a measure of the degree of oxidation of an atom in a chemical compound. The oxidation state can be determined by assigning electrons to each atom in a compound according to a set of rules.
In general, carbon (C) exhibits an oxidation state of -4 in compounds such as methane (CH₄), where it is bonded to four hydrogen atoms. Carbon can also exhibit positive oxidation states in compounds such as carbon dioxide (CO₂), where it is bonded to two oxygen atoms, and in carbonyl compounds, where it is bonded to a metal.
Silicon (Si), germanium (Ge), tin (Sn), and lead (Pb) all belong to the same group in the periodic table and therefore exhibit similar chemical properties. They can all exhibit positive oxidation states of +2 and +4. For example, silicon can exhibit an oxidation state of +4 in silicon dioxide (SiO₂) and +2 in silane (SiH₄). Germanium, tin, and lead also exhibit a similar range of oxidation states in their compounds.
To know more about oxidation states, refer here:
https://brainly.com/question/31688257#
#SPJ11
How many grams of sodium sulfate are needed to prepare 750. ML of a
0. 375 M solution? (**Use only numerical answers with 3 significant figures.
The units are given in the question. )
Voir
We need 39.9 grams of sodium sulfate to prepare 750 mL of a 0.375 M solution.
Volume of the solution = 750 mL = 0.750 L
We know that, moles of solute = molarity × volume of solution (in L)
moles of sodium sulfate = 0.375 M × 0.750 L = 0.281 mol
Molar mass of sodium sulfate ([tex]Na_{2}SO_{4}[/tex])= (2 × 22.99 g/mol) + (4 × 16.00 g/mol) + (32.07 g/mol) = 142.04 g/mol
Therefore, grams of [tex]Na_{2}SO_{4}[/tex] = moles of [tex]Na_{2}SO_{4}[/tex] × molar mass of [tex]Na_{2}SO_{4}[/tex] = 0.281 mol × 142.04 g/mol = 39.9 g
We need 39.9 grams of sodium sulfate to prepare 750 mL of a 0.375 M solution.
To know more about molarity visit:
https://brainly.com/question/8732513
#SPJ11
If 15.0 ml of a 0.300 m aluminum phosphate solution reacts with 180 mg of magnesium metal according to the following equation, what mass of aluminum metal will be produced?
The mass of aluminum metal produced when 15.0 mL of a 0.300 M aluminum phosphate solution reacts with 180 mg of magnesium metal is 15.60 mg.
1. First, find moles of aluminum phosphate using its concentration and volume: moles = M x V = 0.300 mol/L x 0.015 L = 0.0045 mol.
2. Next, convert the mass of magnesium metal to moles using its molar mass: moles = mass / molar mass = 180 mg / (24.31 g/mol x 1000 mg/g) = 0.00741 mol.
3. Now, find the limiting reactant by comparing the mole ratios: (0.0045 mol AlPO₄) / (2) < (0.00741 mol Mg) / (3), so aluminum phosphate is the limiting reactant.
4. Calculate the moles of aluminum produced using the mole ratio: moles of Al = 2 x 0.0045 mol AlPO₄ = 0.009 mol.
5. Finally, convert the moles of aluminum to mass: mass = moles x molar mass = 0.009 mol x 26.98 g/mol x 1000 mg/g = 15.60 mg.
To know more about limiting reactant click on below link:
https://brainly.com/question/14225536#
#SPJ11