Answers
Answer:9.012
Explanation:
I used the periodic table, the mass is 9.012
Answer:
Pretty sure it would be 69(nice).
Explanation:
You add the number of protons and neutrons to find the mass
Related Questions
What is the correct order for the three steps of how a hormone would work
A. Response > Reception > Transduction.
B. Reception > Response > Transduction.
C. Reception > Transduction > Response.
D. Transduction Response > Signaling.
Answers
Answer:
answers is -d
Explanation:
,kggc’hnftfj’trudging.ugu,y
Number of atoms in 2.56 moles of He
Answers
1.54 × 10²⁴ atoms He
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Atomic Structure
MolesAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Stoichiometry
Using Dimensional AnalysisExplanation:Step 1: Define
[Given] 2.56 moles He
[Solve] atoms He
Step 2: Identify Conversions
Avogadro's Number
Step 3: Convert
[DA] Set up: [tex]\displaystyle 2.56 \ mol \ He(\frac{6.022 \cdot 10^{23} \ atoms \ He}{1 \ mol \ He})[/tex][DA] Multiply [Cancel out units]: [tex]\displaystyle 1.54163 \cdot 10^{24} \ atoms \ He[/tex]Step 4: Check
Follow sig fig rules and round. We are given 3 sig figs.
1.54163 × 10²⁴ atoms He ≈ 1.54 × 10²⁴ atoms He
1. What is a forensic palyn ologist?
2. Describe the case that Mildenhall worked on in New Zealand.
3. How can a forensic palynologist help a crime investigation?
4. What are the challenges of using a forensic palynologist in crime investigations?
Answers
Answer:
A forensic palynologist is a spore and pollen expert that helps solve crimes.
The case that Mildenhall worked on was about a murder that involved a prostitute. The police couldn’t find a trace to help solve the case, so they called Mildenhall to help with pollen clues. He was able to find trace evidence in the pollen, which helped police connect the victim to a gang hangout by the crime scene.
A forensic palynologist can help with a criminal investigation by comparing pollen from the suspect and the victim using a comparison microscope to determine if the pollen matches.
The challenges of using a forensic palynologist in a criminal investigation are that judges and juries may have a hard time understanding palynologists.
Explanation:
Answers of the following points regarding forensic palynologist are given below:
What is forensic palynology?This is a internal branch of palynology that deals with the relationship among different objects to prove or disprove, which may belongs to both criminal and civil cases.
(1). Forensic palynologist is a person who do the case study of the crime seen, and deals with a spore and pollen.
(2). Mildenhall worked on a murder case in New Zealand where a prostitute was involved. Police were not able to solve the crime, so they called Mildenhall to help with pollen clues. Mildenhall who is a spore and pollen expert was able to study the pollen clues and gave hint to the police as they were do further process to connect with the victim.
(3). A forensic palynologist by comparing the pollen clues from the crime scene and the victim, can help with a criminal investigation by using a comparison microscope to determine if the pollen matches.
(4). As forensic palynology is a science study which can not be general understand by normal people; so that judges, juries and advocates may have a hard time understanding palynologists and this is the challenges of using a forensic palynologist in crime investigations.
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For most substances the density of a solid form is slightly greater than the density of liquid form water however is different it is slightly less dense in the solid form than it is in liquid form compare water in the solid form with neon argon in oxygen and proposal reason why solid water is less dense liquid water
Answers
Answer:
Answer: When water freezes, water molecules form a crystalline structure maintained by hydrogen bonding. Solid water, or ice, is less dense than liquid water. Ice is less dense than water because the orientation of hydrogen bonds causes molecules to push farther apart, which lowers the density.
Explanation:
A rigid container has 44.5 grams of oxygen gas at room temperature and a pressure of 2.3 atm. How many grams of oxygen should the container have for the pressure to be 7.8 atm?
Answers
Answer:
The mass of oxygen the container must have is 150.85 g.
Explanation:
Given;
mass of the oxygen, m₁ = 44.5 g
initial pressure of the gas, P₁ = 2.3 atm
final pressure of the gas, P₂ = 7.8 atm
Atomic mass of oxygen gas, = O₂ = 16 x 2 = 32 g
initial number of moles of oxygen in the container, n₁ = 44.5/32 = 1.39
let the final number of moles of oxygen = n₂
Apply ideal gas equation;
PV = nRT
[tex]\frac{PV}{Rn} = T\\\\since \ temperature\ T \ is \ constant;\\\\\frac{P_1V}{Rn_1} = \frac{P_2V}{Rn_2}\\\\\frac{P_1}{n_1} = \frac{P_2}{n_2} \\\\n_2 = \frac{n_1P_2}{P_1} \\\\n_2 = \frac{1.39 \times 7.8}{2.3} \\\\n_2 = 4.714 \ moles[/tex]
The mass of the oxygen in grams is calculated as;
m₂ = 4.714 x 32g
m₂ = 150.85 g
Therefore, the mass of oxygen the container must have is 150.85 g.
Local winds can be caused by______heating of the earth's surface.
equal
ground
uneven
super
Answers
How many moles are in 6.34 x 10^24 molecules of ZnCl2?
Answers
Answer:
10.53 moles ZnCl2
Explanation:
Both amines and amides are derivatives of
acetic acid
sodium hydroxide
ammonia
sodium chloride
Answers
Answer:
Ammonia
Explanation:
Both amines and amides are structurally similar to ammonia, the difference is the introduction of a carbon into the structure.
What does a wider tree ring indicate as opposed to a thinner tree ring
Answers
Answer:
Thicker rings indicate a longer or faster growing season. This means that the temperature was high for a longer time and allowed the tree to grow more. Smaller rings show shorter or slower growing seasons which means either the temperature was low or the tree didn't have enough water to grow very much.
Explanation:
Hoped that helped!
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Question : How many moles of O2 are in the sample of 3.6 kilograms of air if 21% of the air is oxygen O2 by mass?
Answers
Answer:
47.25 moles
Explanation:
First we find the amount of O2 in mass in air
That will be = (21/100) x 3.6
This will give us=0.756 kg
Now we want to find the moles, so we convert this mass into grams since we are going to be working with grams= 0.756 x 1000 = 756 grams
Now, to find the number of moles:
moles= mass / molar mass
in this case mass is 756 grams and molar mass of oxygen is 16
So, the mass divided by molar mass would be =756/16= 47.25 moles of O2
A biochemist prepares a 1 L solution using 12.1 g of Tris Buffer. The final concentration is 0.1 M. What is the MW of Tris Buffer?
Answers
Answer: The molecular weight of tris buffer is 121 g/mol
Explanation:
Molarity of a solution is defined as the number of moles of solute dissolved per liter of the solution.
[tex]Molarity=\frac{n}{V_s}[/tex]
where,
n = moles of solute
[tex]V_s[/tex] = volume of solution in L
moles of tris buffer = [tex]\frac{\text {given mass}}{\text {Molar mass}}=\frac{12.1g}{Mg/mol}[/tex]
Now put all the given values in the formula of molality, we get
[tex]0.1=\frac{12.1g}{Mg/mol\times 1L}[/tex]
[tex]M=121g/mol[/tex]
Therefore, the molecular weight of tris buffer is 121 g/mol
1. How many grams does 10 moles of Carbon weigh?
Answers
Answer:120
Explanation: I think
Answer:
1321.177 grams.
Explanation:
each mole of carbon is 12.0107 grams.
does a mole of hydrogen have the same mass as a mole of oxygen? explain your answer
Answers
AlCl3(s)+Ca3N2(s)→AlN(s)+CaCl2(s)
Answers
Answer:
the subject of a talk, piece of writing, exhibition, etc.; a topic.
Explanation:
Answer:
1 NH4NO3(s) → 1 N2(g) + 4 H2O(g) + 2 O2(g)
Explanation:
The molecular-orbital model for Ge shows it to be:_______.
A) a conductor, because all the lower energy band orbitals are filled and the gap between the lower and higher bands is large.
B) an insulator, because all the lower energy band orbitals are filled and the gap between the lower and higher bands is large.
C) a semiconductor, because the gap between the filled lower and empty higher energy bands is relatively small.
D) a semiconductor, because the gap between the filled lower and empty higher energy bands is large.
E) a conductor, because its lower energy band orbitals are only partially filled.
Answers
Answer:
Option C
Explanation:
Pure germanium is a bad conductors of electricity. It is so because its valence band is full and its outer electrons are attached through covalent bond is a diamond like framework. In metallic sense, it is neither a conductor nor an insulator but a semiconductor. It has a small band gap of 0.7eV.
Hence, option C is correct
Determine whether each observation generally corresponds to a physical change or a chemical change. A liquid freezes into a solid. _________ Bubbles are produced upon mixing two solutions. __________ A precipitate is formed from two solutions. _________ A solution heats up upon mixing with another. ____________ A solid dissolves into water. __________ The color of a substance changes over time
Answers
Answer:
A liquid freezes into a solid or any other state change is a physical change. Bubbles are produced upon mixing two solutions is a Chemical change as gas formed. a precipitate is formed from two solutions is a Chemical change The conversion of a substance to another compound over time leads to a color change of the substance due to the insolubility of the compound.
It is a chemical change or properties. A solution that heats up upon mixing with another is a Chemical change known as an exothermic reaction. dissolving the substance in a liquid is a physical change physical that can be regained by evaporation or crystalization.
Sodium azide (NaN3) is a substance that can be used to inflate airbags. An electrical impulse causes the sodium azide to decompose, producing elemental sodium and nitrogen gas. Write the balanced chemical equation for this reaction.
Answers
Answer:
2NaN₃ → 2Na + 3N₂
Explanation:
First we use the information given by the problem to write an unbalanced equation:
NaN₃ → Na + N₂There are 3 N atoms on the left side and only 2 on the right, to remedy that we put a 2 coefficient on NaN₃ and a 3 coefficient on N₂:
2NaN₃ → Na + 3N₂Now there are 6 N atoms on both sides of the equation. What's left is to balance Na atoms:
2NaN₃ → 2Na + 3N₂The equation is now balanced.
The properly balanced chemical equation for this chemical reaction is given by [tex]2NaN_3 \rightarrow 2Na + 3N_2[/tex]
What is a balanced chemical equation?
A balanced chemical equation can be defined as a chemical equation wherein the number of atoms on the reactant side (left) is equal to the number of atoms on the product side (right).
In this scenario, Sodium azide ([tex]NaN_3[/tex]) undergoes a decomposition reaction due to an electrical impulse, which causes it to produce elemental sodium and nitrogen gas.
The properly balanced chemical equation for this chemical reaction is given by:
[tex]2NaN_3 \rightarrow 2Na + 3N_2[/tex]
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3. Noble gases are sometimes called "inert gases." What can you infer about the meaning of the word "inert" in chemistry?
Answers
Answer:
Noble gases are sometimes called "inert gases." What can you infer about the meaning of the word "inert" in chemistry? It refers to substances that easily lose electrons. It refers to substances that do not react with other substances. It refers to substances that have strong electrochemical charges.
Explanation:
In liquids, the attractive intermolecular forces are ________. In liquids, the attractive intermolecular forces are ________. strong enough to keep the molecules confined to vibrating about their fixed lattice points strong enough to hold molecules relatively close together strong enough to hold molecules relatively close together but not strong enough to keep molecules from moving past each other not strong enough to keep molecules from moving past each other
Answers
Answer:
strong enough to hold molecules relatively close together but not strong enough to keep molecules from moving past each other.
Explanation:
In liquids, the attractive intermolecular forces are strong enough to hold molecules relatively close together but not strong enough to keep molecules from moving past each other.
Intermolecular forces are the forces of repulsion or attraction.
Intermolecular forces lie between atoms, molecules, or ions. Intramolecular forces are strong in comparison to these forces.
In liquids, the attractive intermolecular forces are strong enough to hold
molecules relatively close together but not strong enough to keep
molecules from moving past each other.
Liquid is a state of matter in which the atoms are relatively close to each
other but less than that of solids which are densely and tightly packed.
The intermolecular force in liquids are strong enough to hold them together
which makes them less easily compressible but not strong enough to keep
them from moving or gliding past each other because they aren't tightly
packed.
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Which of the following is evidence that a chemical
change is occurring?
a. Cherry drink mix is added to water and the resulting
solution is red.
b. A white powder is added to cool tap water in a beaker
and the beaker gets hot.
c. Water is added to coffee until the solution becomes
clear.
d. Water is added to sand and the sand looks darker
Answers
Answer:
c. water is added to coffe until the solution becomes clear
Answer:
c
Explanation:
Water is added to coffee until the solution becomes
clear.
How are stars and comets different?
A star has a solid rock and gas surface, while a comet has tail of dust and gas.
A star has a tail of dust and gas, while a comet has a solid rock surface.
A star is made up of burning gases, while a comet is made up of ice, gases, rocks, and dust.
A star is made up of ice, rocks, and dust, while a comet is made up of burning gases.
Answers
Answer:
Explanation:
The main difference between these two is that a star has a solid rock and gas surface, while a comet has tail of dust and gas. A star is a giant mass of rock and gas that follows a set eliptical path. Comets on the other hand are made of ice and dust with some gases and usually travel in a straight path. This is why they have a tail of dust and gas which is the ice burning up behind it as it travels at extremely high speeds.
Answer: A: A star has a solid rock and gas surface, while a comet has tail of dust and gas.
Explanation:
3. A very large distillation column is separating p-xylene (more volatile) from o-xylene. The column has two feeds that are saturated liquids. Feed 1 flows into the column at a rate of 90 kmol/h and contains 42 mol% p-xylene. Feed 2 flows at a rate of 20 kmol/h and contains 9 mol% p-xylene. The bottoms product should be 97 mol% o-xylene, and the distillate product should be 99 mol% p-xylene. Compute the distillate (D) and the bottoms (B) products flow rates
Answers
Answer:
the distillate (D) and the bottoms (B) products flow rates are;
B = 72.1875 kmol/hr
D = 37.8125 kmol/hr
Explanation:
Given the data in the question;
as illustrated in the image below;
F1 stream, ( 90 kmol/hr ) contains 42 mol% p-xylene and Feed 2 ( 20 kmol/hr) contains 9mol% p-xylene, so;
more volatile → p-xylene
less volatile → o-xylene
now, Overall balance;
F1 + F2 = D + B
90 + 20 = D + B
D + B = 110 ------------- let this be equation 1
p-xylene. component balance;
0.42F1 + 0.09F2 = 0.99D + 0.03B
0.42(90) + 0.09(20) = 0.99D + 0.03B
37.8 + 1.8 = 0.99D + 0.03B
0.99D + 0.03B = 39.6 --------------- let this be equation 2
from equation 1 and 2
input (D = 110 - B) into equation 2
0.99(110 - B) + 0.03B = 39.6
108.9 - 0.99B + 0.03B = 39.6
108.9 - 39.6 = 0.99B - 0.03B
69.3 = 0.96B
B = 69.3 / 0.96
B = 72.1875
now, input B = 72.1875 into equation 1
D + B = 110
D + 72.1875 = 110
D = 110 - 72.1875
D = 37.8125
Therefore, the distillate (D) and the bottoms (B) products flow rates are;
B = 72.1875 kmol/hr
D = 37.8125 kmol/hr
How many moles in 2.33E25 molecules of NO?
0.0258 mol
3.87E20 mol
38.7 mol
2.58E48 mol
please show work
Answers
Answer:
0.0258 mol Answer .......
Suppose you want to prepare a buffer with a pH of 4.59 using formic acid. What ratio of [sodium formate]/[formic acid) do you need to make this buffer? Formic acid has a K, of 1.8x10 4 Enter your answer to three significant figures.
Answers
Answer:
7.08
Explanation:
To solve this problem we'll use the Henderson-Hasselbach equation:
pH = pka + log[tex]\frac{[A^-]}{[HA]}[/tex]Where [tex]\frac{[A^-]}{[HA]}[/tex] is the ratio of [sodium formate]/[formic acid] and pka is equal to -log(Ka), meaning that:
pka = -log (1.8x10⁻⁴) = 3.74We input the data:
4.59 = 3.74 + log[tex]\frac{[A^-]}{[HA]}[/tex]And solve for [tex]\frac{[A^-]}{[HA]}[/tex]:
0.85 = log[tex]\frac{[A^-]}{[HA]}[/tex][tex]10^{(0.85)}[/tex]=[tex]\frac{[A^-]}{[HA]}[/tex][tex]\frac{[A^-]}{[HA]}[/tex] = 7.08The ratio of [sodium formate] to [formic acid] needed to make the buffer is 7.08
How to determine the pKaEquilibrium constant (Ka) = 1.8×10¯⁴pKa =?pKa = –Log Ka
pKa = –Log 1.8×10¯⁴
pKa = 3.74
How to determine the ratio of [sodium formate] to [formic acid]pH = 4.59pKa = 3.74Ratio of [sodium formate] to [formic acid] =?pH = pKa + Log[sodium formate]/[formic acid]
4.59 = 3.74 + Log[sodium formate]/[formic acid]
Collect like terms
4.59 – 3.74 = Log[sodium formate]/[formic acid]
0.85 = Log[sodium formate]/[formic acid]
Take the anti-log of 0.85
[sodium formate]/[formic acid] = anti-log 0.85
[sodium formate]/[formic acid] = 7.08
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in the photosynthesis the energy starts as ___ energy and ends up as___energy
light heat
chemical: chemical
heat light
light chemical
Answers
Answer: Light, Chemical
Explanation: This is the answer because "photosynthesis takes place in two stages: the light-dependent reactions and the Calvin cycle. In the light-dependent reactions, which take place at the thylakoid membrane, chlorophyll absorbs energy from sunlight and then converts it into chemical energy with the use of water." - source https://opentextbc.ca/
In the photosynthesis the energy starts as Light energy and ends up as Chemical Energy. Hence option (D) is correct
What is Photosynthesis ?The process by that inexperienced plants and a few different organisms use daylight to synthesize nutrients from carbonic acid gas and water. chemical action in plants usually involves the inexperienced pigment and generates element as a by-product.
Photosynthesis may be a method employed by plants and different organisms to convert lightweight energy into energy that, through internal respiration, will later be discharged to fuel the organism's activities.
photosynthesis takes place in 2 stages: the light-dependent reactions and also the Calvin cycle. within the light-dependent reactions, that manifest itself at the thylakoid membrane, pigment absorbs energy from daylight and so converts it into energy with the employment of water.
Therefore, In the photosynthesis the energy starts as Light energy and ends up as Chemical Energy. Hence option (D) is correct
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In the morning, a paintball pressure tank is at 306 atm. The weather heats up over the
course of the day, and by 3 PM, the outside temperature is roasting at 38.5°C, and the
pressure inside the tank is 324 atm. What was the temperature (in degree Celsius) in the
morning?
Answers
How many moles of electrons are required for denitrifying organism to reduce 78 moles of nitrate to dinitrogen gas?
Answers
Answer:
780 moles e⁻
Explanation:
N⁺⁵ in NO₃⁻ requires 2(5e⁻) => 1/2 mole N₂(g)
That is, NO₃⁻ + 2(5e⁻/mole N₂ formed) => 1/2N₂
NO₃⁻ + 10e⁻/mole N₂ formed => 1/2N₂
∴ 78 mole NO₃⁻ requires 780 moles e⁻ => 1/2(78) moles N₂ = 39 moles N₂
Denitrification is the reduction of nitrate to dinitrogen gas. It is achieved by denitrifying organism According to stoichiometry, 390 moles of electrons are required to reduce 78 moles of nitrate to dinitrogen gas.
The equation of denitrification;
2 NO3− + 10 e− + 12 H+ → N2 + 6 H2O
From this equation;
2 moles of nitrate requires 10 moles of electrons
78 moles of nitrate requires 78 * 10/2 = 390 moles of electrons
Hence, 390 moles of electrons are required to reduce 78 moles of nitrate to dinitrogen gas.
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help?
A 22.98 g sample of a compound contains 7.33 g of potassium, K, 6.65 g of chlorine, Cl, and oxygen, O. Calculate the empirical formula.
Insert subscripts as needed.
Empirical formula: KClO
Answers
Answer:
[tex]KClO_3[/tex]
Explanation:
Hello!
In this case, as we know the mass of the total sample, we can first compute the mass of oxygen:
[tex]m_O=22.9g-7.33g-6.65g=8.92g[/tex]
Next, we compute the moles of each element:
[tex]n_K=\frac{7.33g}{39.9g/mol}= 0.184mol\\\\n_{Cl}=\frac{6.65g}{35.45g/mol}=0.188mol \\\\n_O=\frac{8.92g}{16.00g/mol} =0.5575mol[/tex]
Now, we divide the moles by 0.184 moles, the fewest ones, to obtain:
[tex]K=\frac{0.184}{0.184}=1.0 \\\\Cl=\frac{0.187}{0.184}=1.0\\\\O=\frac{0.5575}{0.184} =3.0[/tex]
Therefore, the empirical formula is:
[tex]KClO_3[/tex]
Regards!
How are people and the landscape impacted by earthquake?
Answers
they are impacted because people loose their home due to the wreckage that has happend and landscapes are ruined due to landslides
Answer:
Well the landscape is torn up, it goes through quite a bit of damage. the plants, animals, and water are all affected by it. when a earth quake hits it destroyes most everything, houses fall into the ground and are destroyed, people die. Earthquakes destry electrical wires and many other things
Explanation:
Sorry I did not answer it full, but you can look it up online.
Use the solubility generalizations on the information page to predict if one or more precipitates will form when aqueous solutions of zinc chloride (ZnCl2) and sodium carbonate (Na2CO3) are mixed. Write the formula of any precipitate that could form.
Answers
Answer: The formula for the precipitate formed is [tex]ZnCO_3[/tex]
Explanation:
A double displacement reaction is one in which exchange of ions take place. The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.
A double displacement reaction in which one of the product is formed as a solid is called as precipitation reaction.
The balanced chemical equation when aqueous solutions of zinc chloride and sodium carbonate are mixed:
[tex]ZnCl_2(aq)+Na_2CO_3(aq)\rightarrow ZnCO_3(s)+2NaCl(aq)[/tex]
