Answers
Answer:
C a chemical has become a different color
Explanation:
is it a chemical change when water turns to ice? or to water vapor? no because it can easily change back.
it's not A obviously
I just explained why it's not B
and again it's obviously not D
It's C because once you change the color of something you can most likely not change it back (cake batter, stained glass) making it a chemical change
Related Questions
Literally struggling with this concept.(problem set included below)
Answers
2. Do a mole to mole ratio of the limiting reactant to the product you want to find
3. Change the result from step 2 from moles to grams.
I know this is broad. If you have trouble with a specific step in this process I will go more in depth. Just let me know :)
You make up a solution of a diprotic acid, H2A, having pKa values of 5.0 and 9.0. Identify the primary, secondary, and tertiary species when you set the pH equal to 8.0 by addition of KOH.
Answers
Answer:
Explanation:
A solution with a pH value of 7 is neutral i.e neither acidic nor alkaline. A solution with a pH less than 7 is said to be acidic, while one with a pH value more than 7 is alkaline. Acidity increases as the value decrease below 7, while alkalinity increases as the value increase about 7.
Given that H2A is a diprotic weak acid have pKa values of 5.0 ad 9.0, it will undergo dissociation in the solution as:
NOTE: These reactions are reversible reactions.
[tex]\mathbf{H_2A \to H^+ + HA^- \ \ \ pKa = 5.0}[/tex]
[tex]\mathbf{HA^- \to H^+ +A^{2-} \ \ \ pKa = 9.0}[/tex]
Thus;
The primary species is HA⁻
The secondary species is A²⁻
what is the oxidation number of cesium in Cs2Cr2O7
Answers
+1 for each Cs, -2 for each O, +6 for each Cr
When you finish exercising, you are hot, tired, and sweating. After a bottle of juice, you feel a lot better. Which organ systems are working together in this scenario?
Answers
Answer:
Nervous and Excretory
Explanation:
The nervous system makes you thirsty. The integumentary system makes you sweat. the integumentary system is very similar to the Excretory system.
Nervous and Excretory systems are working together in this scenario.
The nervous system makes you thirsty. The integumentary system makes you sweat. the integumentary system is very similar to the Excretory system.
The blood flow increases, your brain is exposed to more oxygen and nutrients. Exercise also induces the release of beneficial proteins in the brain. Sweating cools the body when it becomes warm. When the body temperature rises, such as when exercising on a hot day, the dermal blood vessels dilate.The excretory system works with the endocrine system to help maintain homeostasis.Learn more:
brainly.com/question/17342396
How many moles are found in 10.5 g of Pb?
Answers
Answer:
Number of moles = 0.05 mol
Explanation:
Given data:
Mass of Pb = 10.5 g
Number of moles of Pb = ?
Solution:
Formula:
Number of moles = mass/molar mass
Molar mass of Pb is 207.2 g/mol.
Now we will put the values in formula.
Number of moles = 10.5 g/207.2 g/mol
Number of moles = 0.05 mol
Two fruit flies that are heterozygous for body color and eye color are crossed. Brown body color is dominant to black body color. Red eye color is dominant to brown eye color.
Determine the genotypes of offspring 1-8.
1
2
3
4
5
6
7
8
A 4-column table has 4 rows. The labels of the columns are Upper B Upper E, Upper B e, b Upper E, b e. The labels of the rows are Upper B Upper E, Upper B e, b Upper E, Upper B b Upper E e. The first column has entries 1, Upper B Upper B Upper E e, 4, Upper B b Upper E e. The second column has entries Upper B Upper B Upper E e, 3, Upper B b Upper E e, 7. The third column has entries Upper B b Upper E Upper E, Upper B b Upper E e, 5, b b Upper E e. The fourth column has entries 2,Upper B b e e, 6, 8.
Answers
Answer:
the answer is simple
Explanation:
jnnn B upper up of the eye color
Answer:
1. BBEE
2. BbEe
3. BBee
4. BbEE
5. bbEE
6. bbEe
7. Bbee
8.bbee
What is the name???????
Answers
Answer:
Carbon Hydrogen
Explanation:
I believe it means carbon (C) to one atom of hydrogen (H).
Cis-3-tert-Butylcyclohexanol has the tert-butyl group in the equatorial position and the alcohol in the ________ position.
Answers
Answer:
Axial
Explanation:
In the most stable conformation of Cis-3-tert-Butylcyclohexanol, the tert-butyl group is at equatorial position and the alcohol group is in the axial position.
If the tert-butyl group is placed in equatorial position, repulsions are minimized. The bulkier the group, the greater the energy difference between the axial and equatorial conformers. Hence for a ring having a bulky substituent, such bulky substituent is better placed in the equatorial position.
The energy difference between the conformers of Cis-3-tert-Butylcyclohexanol is so high that the compound is almost "frozen" in a conformation where the tert-butyl groups are equatorial and the -OH groups are axial. This conformer is more stable by 24 KJ/mol.
Cis-3-tert-Butylcyclohexanol has the molecular formula of [tex](\rm C_{10}H_{20}O)[/tex]. The alcohol group in the compound is found at the axial position.
What are the groups and their positions?In the compound Cis-3-tert-Butylcyclohexanol alcohol is the functional group present at the axial position and tert-butyl group at the equatorial position of the compound.
Tert-butyl group at the equatorial position minimizes the repulsive forces and are bulky groups, the position of the bulkier groups at the equatorial positions are better as the energy differences will be large.
The difference in the energy of the conformers of the compound is high and the conformation of the compound remains as it is.
Therefore, tert-butyl groups are at equatorial and the alcohol groups are at axial.
Learn more about equatorial and axial positions here:
https://brainly.com/question/10696788
In the situations described below, what is the free energy change if 1 mole of Na+ is transported across a membrane from a region where the concentration is 267 μM to a region where it is 80 mM? (Assume T=37∘C.)
Answers
Answer:
ΔG = 19.5 kJ/mol
Explanation:
The free energy change for moving an ion is given by the following formula:
ΔG = RT㏑(C₂/C₁) + ΖЭψ
where R is molar gas constant = 8.315 J/mol;
T = 273 +37 = 310 K;
C₂ is concentration outside the cell = 267 μM = 0.000267 M;
C₁ is concentration inside the cell = 80 mM = 0.005 M;
Ζ is charge on ion = +1;
Э is Faraday's constant = 96500 J/V;
ψ is standard transmembrane potential = 0.05 V
ΔG = (8.315 J/mol * 310 K) ㏑(0.08/0.000267) + 1 *(96500 J/V * 0.05 V)
ΔG = (14692.60 + 4825)J/mol
ΔG = 19517.6 J/mol
ΔG = 19.5 kJ/mol
A sample of methane gas is collected at 285 K and cooled to 245 K. At 245 K the volume of the gas is 75.0 L. Calculate the volume of the methane gas at 285 K. Assume constant pressure
Answers
Answer:
V₂ = 87.24 L
Explanation:
Charle's law states that at constant pressure, the volume of the gas is directly proportional to the temperature. Its mathematical form is given by :
[tex]\dfrac{V_1}{T_1}=\dfrac{V_2}{T_2}[/tex]
We have, V₁ = 75, T₁ = 245 K, T₂ = 285, V₂ = ?
Putting all the values, we get :
[tex]V_2=\dfrac{V_1T_2}{T_1}\\\\V_2=\dfrac{75\times 285}{245}\\\\V_2=87.24\ L[/tex]
So, the new volume is 87.24 L.
what is the point of doing an experiment. Help thank you
Answers
Answer:
to find out how somethings work
Explanation:
Answer:
Doing experiments is good because when you try these possibilities you can learn about something that you've tried or see why this experiment didn't really work. It also helps you understand that not everything you try will work. that's why we experiment.
Explanation:
Hope this helps:)
Which graph best matches a person walking away at a constant speed
Answers
What might a peasized gland within the skull be?
salivary gland
pituitary gland
mammary gland
sebaceous gland
Answers
Answer:
Explanation:
pituitary gland
Answer:
B
Explanation:
The pituitary gland is a pea-sized structure that is attached to the undersurface of the brain by a thin stalk.
Cathode rays are deflected toward a negatively charged plate in an electric field.
True
False
Answers
Answer:
true. cathode rays are deflected
how many atoms are in 20.34 grams of aluminum (Al)
A) 6.02 x 10^23 atoms
B) 4.54 x 10^23 atoms
C) 4.54 atoms
D) 548.8 grams
Answers
Notice that the value 12.01 grams of natural carbon is the same as the atomic mass value (12.01 amu). It also tells us that 20.34 grams of aluminum contains exactly 6.022 x 1023 atoms of aluminum.
✅
So, the answer is A) 6.02 x 10^23 atoms
IamSugarBee
Answer:
Option A: 6.03 * 10^23 atoms
What are the factors affecting your limitations? How about possibilities?
Answers
Explanation:
My physiological make-up that governs the attributes I have and my climate, i.e. the conditions I have, are the variables influencing my limits. Biological make-up also regulates my prospects when they depend on my attributes, i.e. my ability and my environment , i.e. the conditions under which I am. This has been shown by experiments on twins, that our limits and opportunities are controlled by both genetics and environment.
The half life of oxygen is 2 minutes. What fraction of a sample of 0.15 will remain after 5 half lives?
Answers
Answer:
3.13%.
Explanation:
The following data were obtained from the question:
Original amount (N₀) = 0.15
Half life (t½) = 2 mins
Number of half-life (n) = 5
Fraction of sample remaining =.?
Next, we shall determine the amount remaining (N) after 5 half-life. This can be obtained as follow:
Amount remaining (N) = 1/2ⁿ × original amount (N₀)
NOTE: n is the number of half-life.
N = 1/2ⁿ × N₀
N = 1/2⁵ × 0.15
N = 1/32 × 0.15
N = 0.15/32
N = 4.69×10¯³
Therefore, 4.69×10¯³ is remaining after 5 half-life.
Finally, we shall the fraction of the sample remaining after 5 half-life as follow:
Original amount (N₀) = 0.15
Amount remaining (N) = 4.69×10¯³
Fraction remaining = N/N₀ × 100
Fraction remaining = 4.69×10¯³/0.15 × 100
Fraction remaining = 3.13%
The density of wind-packed snow is estimated to be 0.35 g/cm^3. A flat roof that is 35 by 43 feet has 28 inches of snow on it. How many pounds of snow are on the roof?
Answers
Answer:
There are 76728.2 pounds of snow on the roof
Explanation:
To determine how many pounds of snow are on the roof,
First we will determine the mass of the snow in grams.
From the question,
Density of snow = 0.35 g/cm³
From
Density = Mass / Volume
To determine the mass, we will first find the volume.
From the question, a flat roof that is 35 by 43 feet has 28 inches of snow on it, that is, the height of the snow on the roof is 28 inches.
Area of the roof = 35 ft × 43 ft = 1505 ft²
Volume of the snow = Area of the roof × Height of the snow
Height of the snow = 28 inches
12 inches = 1 foot
∴ 28 inches = 28/12 feet = 2.3333 ft
Hence,
Volume of the snow = 1505 ft² × 2.3333 ft = 3511.62 ft³
Volume of the snow = 3511.62 ft³
This is the volume of the snow in cubic feet
Now, we will convert cubic feet (ft³) to cubic centimeter (cm³)
1 ft = 30.48 cm
and 1 ft³ = 30.48³ cm³ = 28316.84659 cm³.
If 1 ft³ = 28316.84659 cm³
∴ 3511.62 ft³ will be 3511.62 × 28316.84659 cm³ = 99438004.83 cm³
Hence, Volume of snow = 99438004.83 cm³
Now, we can determine mass of snow in grams
From
Density = Mass / Volume
Mass = Density × Volume
Mass = 0.35 g/cm³ × 99438004.83 cm³
Mass = 34803301.69 g
Now, we will convert the mass from grams to pounds
1 pound = 453.592 grams
If 453.592 grams = 1 pound
Then, 34803301.69 g will be 34803301.69 / 453.592 pounds = 76728.2 pounds
Hence, there are 76728.2 pounds of snow on the roof.
The potential energy of a roller coaster is 50 joules. The kinetic energy of the same coaster is 50 joules. What is the mechanical energy of the coaster? O joules 50 joules 100 joules
Answers
Answer:
100 joules
Explanation:
The mechanical energy (M.E) of an object describes the objects ability to do work. The mechanical energy encompasses the object's energy due to its position (potential energy) and its energy due to motion (kinetic energy).
Therefore,
M.E = K.E + P.E
According to this question, potential energy (P.E) of the roller coaster is 50J and the kinetic energy (K.E) is also 50J. Hence, the mechanical energy (M.E) is
M.E = 50J + 50J
M.E = 100J
If the P.E and K.E of a roller coaster is 50 Joules respectively, the mechanical energy of the roller coaster is 100 Joules.
Given the following data:
Potential energy of roller coaster = 50 Joules.Kinetic energy of roller coaster = 50 Joules.To find the mechanical energy of the roller coaster:
The mechanical energy of a physical object or body is the total sum of the potential energy (P.E) and kinetic energy (K.E) possessed by an object.
Mathematically, mechanical energy is given by the formula;
Substituting the given parameters into the formula, we have;
[tex]M.E = 50 + 50[/tex]
Mechanical energy (M.E) = 100 Joules.
Therefore, the mechanical energy of the roller coaster is 100 Joules.
Read more: https://brainly.com/question/23153766
Identify the correct equation for the equilibrium constant Kc for the reaction given. C u ( s ) + 2 A g N O 3 ( a q ) − ⇀ ↽ − C u ( N O 3 ) 2 ( a q ) + 2 A g ( s ) Cu(s)+2AgNOX3(aq)↽−−⇀Cu(NOX3)X2(aq)+2Ag(s) Select one: K c = [ Cu ( NO 3 ) 2 ] [ Ag ] 2 [ AgNO 3 ] 2 [ Cu ] Kc=[Cu(NO3)2][Ag]2[AgNO3]2[Cu] K c = [ Cu ( NO 3 ) 2 ] 2 [ Ag ] [ AgNO 3 ] [ Cu ] 2 Kc=[Cu(NO3)2]2[Ag][AgNO3][Cu]2 K c = [ Cu ( NO 3 ) 2 ] [ AgNO 3 ] 2 Kc=[Cu(NO3)2][AgNO3]2 K c = [ Cu ( NO 3 ) 2 ] [ AgNO 3 ] Kc=[Cu(NO3)2][AgNO3]
Answers
Answer:
Kc = [Cu(NO₃)₂]/[2 AgNO₃]²
Explanation:
Let's consider the following balanced redox equation.
Cu(s) + 2 AgNO₃(aq) ⇄ Cu(NO₃)₂(aq) + 2 Ag(s)
The concentration equilibrium constant (Kc) is equal to the product of the concentration of the products raised to their stoichiometric coefficients divided by the product of the concentration of the reactants raised to their stoichiometric coefficients. It only includes gases and aqueous species.
The concentration equilibrium constant for this reaction is:
Kc = [Cu(NO₃)₂]/[2 AgNO₃]²
Please help, I really don’t understand this!!!
Answers
Analysing the Question:
We are given the balanced equation:
C₆H₁₂O₆ + 6O₂→ 6CO₂ + 6H₂O
from this equation, we can say that: for every 1 mole of Glucose, we need 6 moles of Oxygen
Moles of Glucose used in the reaction:
Molar mass of Glucose = 180 grams / mol
Given mass of Glucose = 1 gram
Mole of Glucose = Given mass / Molar mass
Moles of Glucose = 1 / 180 moles
Mass of Oxygen required:
We know that for every mole of Glucose, we need 6 moles of Oxygen
So, for 1/180 moles of Glucose, we need 6 / 180 = 1 / 30 moles of Oxygen
Mass of 1 / 30 moles of Oxygen:
Mass = Molar mass * number of moles
Mass of Oxygen = 32 * 1/30
Mass of Oxygen = 32 / 30
Mass of Oxygen = 1.06 grams
Select the word that is incorrect in the paragraph and replace it with a word which makes the statement correct:
Group 2 elements have two valence electrons in their outer shell and are considered metals. In order to form an ion, a Group 2 element will
gain two electrons and form a cation.
Answers
Ions can be made by single element or covalently bonded group of elements. The covalently bonded group of elements is called polyatomic ions or polyatomic atoms. In order to form an ion, a Group 2 element will loose two electrons and form a cation.
What is Ions?Any species that contain charge whether it is positive charge or negative charge is called ions. The example of polyatomic ions are sulfate, phosphate, nitrate etc.
Cation is the species that loose electron and attain positive charge while anion is a species which gain electron and attains negative charge so when anion and cation combine in fixed ration the the overall charge of the molecule is zero that is molecule is neutral, the charge over cation and anion is also called oxidation state. In order to form an ion, a Group 2 element will loose two electrons and form a cation.
Therefore, in order to form an ion, a Group 2 element will
loose two electrons and form a cation.
To learn more about ions, here:
https://brainly.com/question/13692734
#SPJ2
These elements look like steps on the periodic table. They share properties of both metals and nonmetals. Computer chips contain elements from this family.
A) these elements are nonmetals
B) These elements are radioactive
C) these elements are metalloids
D) these elements are metals
Answers
Answer:
The answer would be C the metalloid in computer chips is silicone, it has luster like metal but is brittle like non metal.
Explanation:
These elements look like steps on the periodic table. They share properties of both metals and nonmetals. These elements are metalloids. Thus option C is correct.
What is periodic table?Periodic table is defined as an arrangement of all known elements in order of increasing atomic number and recurrent chemical attributes.
It is also defined as an ordered grouping of the 118 known chemical elements.
Metals are defined as a substance that has a glossy appearance when freshly manufactured, polished, or shattered and conducts electricity and heat reasonably effectively.
Non metals are defined as a natural materials that are physically fragile and do not generate heat or electricity.
Metalloids are defined as a type of chemical element with properties that are mostly intermediate between those of metals and nonmetals.
Thus, these elements look like steps on the periodic table. They share properties of both metals and nonmetals. These elements are metalloids. Thus option C is correct.
To learn more about periodic table, refer to the link below:
https://brainly.com/question/11155928
#SPJ5
How many distinct dichlorination products can result when isobutane is subjected to free radical chlorination?
a. 1
b. 2
c. 3
d. 4
e. 6
Answers
Answer:
c. 3
Explanation:
Dicholorination of tertiary alkane ( i.e. isobutane) is a halogenation reaction which makes it possible to replace the alkyl functional group with halogenated chlorine.
When Isobutane is subjected to free radicals chlorination, three distinct dichlorination can be formed.
The mechanism of the formation of these products can be seen in the image attached below.
Why does sodium chloride form a crystal lattice
Answers
Answer:
Ions of opposite charge strongly attract each other; those of like charges repel. As a result ions in an ionic compound are arranged in a particular manner.
Explanation:
Google is smart
What is the pH of 0.166 M triethylammonium chloride, (C2H5)3NHCl. The Kb of triethylamine, (C2H5)3N, is 5.2 x 10-4.?
Answers
Answer:
5.7
Explanation:
(C₂H₅)₃NHCl dissociates according to the following equation.
(C₂H₅)₃NHCl ⇒ (C₂H₅)₃NH⁺ + Cl⁻
The molar ratio of (C₂H₅)₃NHCl to (C₂H₅)₃NH⁺ is 1:1. Then, the concentration of (C₂H₅)₃NH⁺ is Ca = 0.166 M.
(C₂H₅)₃NH⁺ is the conjugate acid of (C₂H₅)₃N. Given the Kb of (C₂H₅)₃N, we can calculate Ka for (C₂H₅)₃NH⁺ using the following expression.
Ka × Kb = Kw
Ka = Kw / Kb
Ka = 1.0 × 10⁻¹⁴ / 5.2 × 10⁻⁴
Ka = 1.9 × 10⁻¹¹
(C₂H₅)₃NH⁺ dissociates according to the following equation.
(C₂H₅)₃NH⁺ ⇄ (C₂H₅)₃N + H⁺
We can calculate [H⁺] using the following expression.
[H⁺] = √(Ca × Ka) = √(0.166 × 1.9 × 10⁻¹¹) = 1.8 × 10⁻⁶
The pH is:
pH = -log [H⁺] = -log 1.8 × 10⁻⁶ = 5.7
2.28 is the pH of 0.166 M triethylammonium chloride, [tex](C_2H_5)_3NHCl[/tex]. The Kb of triethylamine, [tex](C_2H_5)_3N[/tex], is [tex]5.2 \times 10^{-4}[/tex].
The term "potential of hydrogen" (pH) refers to a solution's acidity or alkalinity. It is a scale from 0 to 14, with 7 representing neutrality. A pH value of 7 or higher suggests alkalinity, whereas one below 7 indicates acidity. Since the pH scale is logarithmic, each number corresponds to a tenfold increase or decrease in acidity or alkalinity. For instance, a pH of 3 solution is ten times more acidic than a pH 4 solution. Similar to this, a pH 10 solution is ten times more alkaline than a pH 9 solution.
[tex](C_2H_5)_3NH^+ (aq) + H_2O (l) \rightarrow (C_2H_5)_3N (aq) + H_3O^+ (aq)[/tex]
Kb = [triethylamine] [[tex]H_3O^+[/tex]] / [triethylammonium chloride]
5.2 x[tex]10^{-4}[/tex] = (x) (x) / (0.166 - x)
x ≈ 5.32 x [tex]10^{-3}[/tex] M.
pH= -log(x)
= -log(5.32 x [tex]10^{-3}[/tex]))
≈ 2.28
To know more about pH, here:
https://brainly.com/question/32258715
#SPJ6
ou are given a solution containing a pair of enantiomers (A and B). Careful measurements show that the solution contains 98% A and 2% B. What is the ee of this solution
Answers
Complete Question
You are given a solution containing a pair of enantiomers (A and B). Careful measurements show that the solution contains 98% A and 2% B. What is the enantiomeric excess?
Answer:
The value is [tex]k = 96 %[/tex]
Explanation:
From the question we are told that
The percentage of enantiomer A is A = 98%
The percentage of enantiomer B is B = 2%
Generally the enantiomeric excess is mathematically represented as
[tex]k = \frac{A -B}{A+B} * 100[/tex]
=> [tex]k = \frac{98 -2}{98+2} * 100[/tex]
=> [tex]k = 96 %[/tex]
i need soon this is due at 10:30 pm its curently 6:00 pm
What is parasitism?
Answers
Answer:
the practice of living as a parasite in or on another organism.
Hope this HELPS!!!
Explanation:
A helium filled blimp will rise just so high into the atmosphere and then stop. Why? Will a smaller blimp rise higher than a larger one, if both are filled to the same pressure?
Answers
Answer:
See explanation
Explanation:
When a helium blimp rises in the atmosphere, a point eventually comes when the buoyancy of the blimp compared to the air it displaces is no longer greater than gravity's pull on the blimp hence it stops rising.
A smaller blimp will rise more than a larger blimp at the same pressure because the weight of the blimp determines the altitude to which it will rise.
Enough of a monoprotic weak acid is dissolved in water to produce a 0.0129 M solution. The pH of the resulting solution is 2.65 . Calculate the Ka for the acid.
Answers
Answer:
Ka = 4.70x10⁻⁴M
Explanation:
The general dissociation of a weak acid, HX, is:
HX(aq) ⇄ H⁺(aq) + X⁻(aq)
And Ka is written as:
Ka = [H⁺] [X⁻] / [HX]
Where [] represents the molar concentration in equilibrium of each specie.
The equilibrium is reached when X of HX is dissociate in X H⁺ and X X⁻, that is:
[HX] = 0.0129M - X
[H⁺] = X
[X⁻] = X
As pH = -log [H⁺]:
10^-pH = [H⁺] = X = 2.239x10⁻³M
Solving:
[HX] = 0.0129M - 2.239x10⁻³M = 0.01066M
[H⁺] = 2.239x10⁻³M
[X⁻] = 2.239x10⁻³M
Ka = [H⁺] [X⁻] / [HX]
Ka = [2.239x10⁻³M] [2.239x10⁻³M] / [0.01066M]
Ka = 4.70x10⁻⁴M
