So, we know the reduction potentials of the electrodes :
Electrode A = -0.21 V
Electrode B = -0.15 V
We want our cell to be spontaneous - this means that the voltage has to be positive. In order to do so, we need to turn the more negative reduction half reaction to be an oxidation half reaction.
-0.21 is more negative than -0.15, so electrode A will be the oxidation half reaction.
Anode is where the oxidation half reaction takes place, so electrode A is the correct answer . A fun way to remember this is An(ode)Ox(idation) = AnOx and Red(uction)Cat(hode) = RedCat
The E° cell will be 0.21 -0.15 V = 0.6 V
How many molecules are in 0.5 grams of ammonia, NH3?
Answer:
I dont no ma men
Explanation:
Sorry cause a dont no
A certain liquid has a normal freezing point of and a freezing point depression constant . A solution is prepared by dissolving some glycine () in of . This solution freezes at . Calculate the mass of that was dissolved.
The question is incomplete, the complete question is:
A certain substance X has a normal freezing point of [tex]-6.4^oC[/tex] and a molal freezing point depression constant [tex]K_f= 3.96^oC.kg/mol[/tex]. A solution is prepared by dissolving some glycine in 950. g of X. This solution freezes at [tex]-13.6^oC[/tex]. Calculate the mass of urea that was dissolved. Round your answer to 2 significant digits.
Answer: 129.66 g of glycine will be dissolved.
Explanation:
Depression in the freezing point is the difference between the freezing point of the pure solvent and the freezing point of the solution.
The expression for the calculation of depression in freezing point is:
[tex]\text{Freezing point of pure solvent}-\text{freezing point of solution}=i\times K_f\times m[/tex]
OR
[tex]\text{Freezing point of pure solvent}-\text{freezing point of solution}=i\times K_f\times \frac{\text{Given mass of solute}\times 1000}{\text{Molar mass of solute}\times \text{Mass of solvent (g)}}[/tex] ....(1)
where,
i = Van't Hoff factor = 1 (for non-electrolytes)
Freezing point of pure solvent = [tex]-6.4^oC[/tex]
Freezing point of solution = [tex]-13.6^oC[/tex]
[tex]K_f[/tex] = freezing point depression constant = [tex]3.96^oC/m[/tex]
[tex]M_{solute}[/tex] = Molar mass of solute (glycine) = 75.07 g/mol
[tex]w_{solvent}[/tex] = Mass of solvent = 950 g
Plugging values in equation 1:
[tex]-6.4-(-13.6)=1\times 3.96\times \frac{\text{Given mass of glycine}\times 1000}{75.07\times 950}\\\\\text{Given mass of glycine}=\frac{7.2\times 75.07\times 950}{1\times 3.96\times 1000}\\\\\text{Given mass of glycine}=129.66g[/tex]
Hence, 129.66 g of glycine will be dissolved.
How does glue, borax, and water turn into slime, scientifically?
How does glue, borax, and water turn into slime, scientifically?
AnswerIt is the matter of time and Weatherg When aqueous solutions of and are mixed, a solid forms. Determine the mass of solid formed when 140.7 mL of 0.1000 M is mixed with an excess of an aqueous solution of .
The question is incomplete, the complete question is:
When aqueous solutions of NaCl and [tex]Pb(NO_3)_2[/tex] are mixed, a solid forms. Determine the mass of solid formed when 140.7 mL of 0.1000 M NaCl is mixed with an excess of an aqueous solution of
Answer: The mass of lead chloride produced is 1.96 g
Explanation:
Molarity is defined as the amount of solute expressed in the number of moles present per liter of solution. The units of molarity are mol/L. The formula used to calculate molarity:
[tex]\text{Molarity of solution}=\frac{\text{Moles of solute}\times 1000}{ \text{Volume of solution (mL)}}[/tex] .....(1)
Given values:
Molarity of NaCl = 0.1000 M
Volume of the solution = 140.7 mL
Putting values in equation 1, we get:
[tex]0.1000=\frac{\text{Moles of NaCl}\times 1000}{140.7}\\\\\text{Moles of NaCl}=\frac{0.1000\times 140.7}{1000}=0.01407mol[/tex]
The chemical equation for the reaction of NaCl and lead nitrate follows:
[tex]Pb(NO_3)_2(aq)+2NaCl(aq)\rightarrow PbCl_2(s)+2NaNO_3(aq)[/tex]
By the stoichiometry of the reaction:
If 2 moles of NaCl produces 1 mole of lead chloride
So, 0.01407 moles of NaCl will produce = [tex]\frac{1}{2}\times 0.01407=0.007035mol[/tex] of lead chloride
The number of moles is defined as the ratio of the mass of a substance to its molar mass.
The equation used is:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex] ......(2)
Molar mass of lead chloride = 278.1 g/mol
Plugging values in equation 2:
[tex]\text{Mass of lead chloride}=(0.007035mol\times 278.1g/mol)=1.96g[/tex]
Hence, the mass of lead chloride produced is 1.96 g
Which of the following releases chemical energy?
A. throwing a basketball
B. a skier on top of a muntain
C. playing a song through headphones
D. burning wood
Answer:
D. burning wood
Explanation: It seems like the only logical answer
Tn chemical reaction, the energy is released is called as chemical energy. The burning wood releases the chemical energy. Therefore, option D is correct.
What is chemical energy ?Chemical energy is the energy that is released when chemical substances engage in a chemical reaction and change into other substances. Batteries, food, and gas are a few examples of chemical energy storage mediums.
Chemical energy, such as that held in the bonds of atoms and molecules, is stored energy. As a result of a chemical process, this energy is released. A substance typically changes into an entirely different substance once its chemical energy has been released.
The body transforms the energy in meals into heat and mechanical energy. Additionally, coal's chemical energy is transformed into electrical energy in power plants. Last but not least, electrolysis is another way that the chemical energy in a battery might generate electricity.
Thus, option D is correct.
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Doc. No.
QMS
Rev. Date
1. In the reaction
P
> M + N
a) The reactants are:
b) The products are:
Answer: In the reaction:
a) The reactants are: P
b) The products are: M and N
Explanation:
The given reaction equation is as follows.
[tex]P \rightarrow M + N[/tex]
Reactants are the species present on the left side on an arrow in a chemical reaction equation.
On the other hand, products are the species which are present on the right side of an arrow in a chemical reaction equation.
Hence, in the given reaction equation P is the reactant. Whereas M and N are the products.
Thus, we can conclude that in the reaction:
a) The reactants are: P
b) The products are: M and N
Once the race had been completed, the students opened their canisters to see if anything remained inside. They wanted to decide if they should modify their techniques for another race. Designs 1, 2, and 3 all still had some solid Alka-Selzter residue in the canister. Design 4 did not. The teacher asked the students to analyze their results as an engineer would. What worked well in the design? What could be improved? Predict what Design Team 3 decided to change.
A)Use hot water
B)Use more water
C)Not to crush the tablet and to use hot water
D)Not to crush the tablet and to use more water
HURRY! GIVING BRAINLY
Answer:
a
Explanation:because i did the test
Discuss the four impure forms of carbon
Various structures, or allotropes, of carbon, are precious stone, graphite, and fullerenes. In jewel, every carbon iota is attached to four other carbon iotas, shaping an unbending construction that makes precious stones hard.
Which of the following compounds is SOLUBLE?
A. SrSO4
B. CaCO3
C. BaS
D. CaCl2
Answer:
A).
Strontium Sulphate is soluble
Distinguish between
real and virtuaI image
Answer:
(Basic )
Real
These are formed in the front side of the mirror.
Virtual
These are assumed to be formed at the backside of the mirror.
Type of lens used
Converging(real)
Diverging(virtual)
Image reception
Image can be appeared on a screen.(Real)
Image appears to be on the mirror or lens itself.
Interaction of light rays Actual Imaginary(Virtual)
Appearance of image
Inverted(Real)
Erect(Virtual)
Formed by
Concave mirror and convex lens.(Real)
Plane, convex mirror and concave lens.(Virtual)
Example
Image on the theater screen.(Real)
Reflection of any object or body on plane mirror.(Virtual)
Having enough folic acid in your system by the early weeks of pregnancy is critical to prevent spina bifida.
Answer:
Yes.
Explanation:
Yes, enough folic acid in the body by the early weeks of pregnancy helps to prevent spina bifida. The body of woman uses folate during the pregnancy which produces red and white blood cells that help your baby to grow. Folate also lowers the risk of neural tube defect (NTD) in the unborn baby. Neural tube defect (NTDs) are the serious birth defects that greatly affect the spinal cord, brain and skull of the baby.
HELPPP
After 25.3 seconds, the concentration of a starting material
was measured to decrease from 2.00 M to 1.17 M.
Answer:
Rate = 0.83M/s
Explanation:
Rate of a chemical reaction is the 'absolute value' of change in concentration per unit time. That is ...
Rate = |Change in concentration / unit time|
= |Δ[Conc]/Δtime|
= |(1.17M -2.00M) / 25.3s|
= |- 0.83M/s|
= 0.83M/s*
------------
*Note: Some scholars define rate of reaction as a 'scaler' quantity having only magnitude as rate of reaction in a physical sense (up, down, right, left) is not definitive. In physical mechanics, rate is assigned a direction and magnitude of action and becomes a 'vector' quantity.
The speed at which the reaction occurs is called the rate of reaction. The rate of reaction for the decreased concentration is 0.83 M/s.
What is the reaction rate?The reaction rate is the increase or decrease in the concentration of the products per unit of time. The formula for a reaction rate is given as,
[tex]\rm Rate = \rm \dfrac {\text{Change in concentration}} {Unit \; time}[/tex]
Given,
Initial concentration = 1.17 m
Final concentration = 2.00 M
Time = 25.3 sec
Substituting values in the above equation:
[tex]\begin{aligned} &= \dfrac{1.17 - 2.0} {25.3}\\\\&= -0.83\\\\&= 0.83 \;\rm M/s\end{aligned}[/tex]
Therefore, 0.83 M/s is the reaction rate.
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CH3CH2CH2CH2CH2NH2 (organic molecule name)
Explanation:
Heterocyclic aromatic amine: The amine nitrogen is part of an aromatic ring. ... Use a number to locate the amino group on the parent chain. The IUPAC name of CH3CH2CH2CH2CH2NH2 is 1-pentylamine.
The name of the compound CH₃CH₂CH₂CH₂CH₂NH₂ is 1-pentylamine.
How are organic compounds named?Organic compounds are named according to the set of rules provided by the international union of pure and applied chemistry (IUPAC). According to it,1) the chain of carbon atoms having highest number of carbon atoms is selected.
2)according to the number of carbon atoms in chain, parent chain is named.
3) Numbering is done in such a way that substituent if present the carbon on which it is present gets the lowest number.
4) The functional group which is present is mentioned as a suffix along with the carbon position on which it is present.
For example,CH₃CH₂CH₂CH₂CH₂NH₂ is named as follows :
1) As there is only one chain present, amine functional group being present it is numbered from the left hand side as the amine group will get the lowest number.
2) The name is given by writing the parent name that is pentane along with the position of amine group which is carbon-1.
Thus, it is named as 1-pentylamine.
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2) Calculate the density of a rod of metal (in g/cm) with a mass of 196.41g, a diameter of 3.10
cm and a height of 7.55 cm. Volume cylinder = rh. Remember the radius is half the length
of the diameter.
Volume =
Density
Answer:56.98496
Explanation:
half if diameter is radius or 1.55 and double the radius is 3.10 or the length of the diameter. you have a height given, so use the radius and heaight to plug it in the circular cylinder calculator and you get 56.98496
Ethylene produced by fermentation has a specific gravity of 0.787 at 25 degree Celsius. What is the volume of 125g of ethanol at this temperature? (The density of water at 25 degree Celsius is 0.997 g/mL)
Answer: The volume of given amount of ethanol at this temperature is 159.44 mL
Explanation:
Specific gravity is given by the formula:
[tex]\text{Specific gravity}=\frac{\text{Density of a substance}}{\text{Density of water}}[/tex]
We are given:
Density of water = 0.997 g/mL
Specific gravity of ethanol = 0.787
Putting values in above equation, we get:
[tex]0.787=\frac{\text{Density of a substance}}{0.997g/mL}\\\\\text{Density of a substance}=(0.787\times 0.997g/mL)=0.784g/mL[/tex]
Density is defined as the ratio of mass and volume of a substance.
[tex]\text{Density}=\frac{\text{Mass}}{\text{Volume}} [/tex] ......(1)
Given values:
Mass of ethanol = 125 g
Density of ethanol = 0.784 g/mL
Putting values in equation 1, we get:
[tex]\text{Volume of ethanol}=\frac{125g}{0.784g/mL}=159.44mL[/tex]
Hence, the volume of given amount of ethanol at this temperature is 159.44 mL
Reaction Progression
Which statement best describes the diagram?
The pathway A-B-D involves a catalyst and is slower than A-C-D.
The pathway A-B-D involves a catalyst and is faster than A-C-D.
The pathway A-C-D involves a catalyst and is slower than A-B-D.
The pathway A-C-D involves a catalyst and is faster than A-B-D
Obtain 2 test tubes. 2. Add 2 mL of animal blood plasma into the first test tube a. Use a pH test strip to measure the pH of the blood plasma. ______
Answer:
7.4
Explanation:
Plasma proteins are part of the buffer systems of blood plasma. Plasma contains both positively and negatively charged amino and carboxyl groups. These compounds' charged portions can attract and link hydrogen(H) and hydroxyl ions(OH-), therefore act as buffers.
Plasma serves as a weak and ineffective buffer. The pH of a buffer should always be around 7.4 which is nearly neutral. As such we may deduce from the first experimental observation that there is no change in pH.
Common decay process definition in your own words
Answer:
Your welcome! :)
Explanation:
THE PROCESS IS: Radioactive decay involves the emission of a particle and/or energy as one atom changes into another. In most instances, the atom changes its identity to become a new element.
THE DEFINITION IS: Decay, decompose, rot, putrefy, spoil mean to undergo destructive dissolution. decay implies a slow change from a state of soundness or perfection. a decaying mansion decompose stresses a breaking down by chemical change and when applied to organic matter a corruption.
Caustic soda, NaOH, can be prepared commercially by the reaction of Na2CO3 with slaked lime, Ca(OH)2. How many grams of NaOH can be obtained by treating 1.350 kg of Na2CO3 with Ca(OH)2
Caustic soda, NaOH, can be prepared commercially by the reaction of Na2CO3 with slaked lime, Ca(OH)2. 1.509 kg of NaOH can be obtained by treating 1.350 kg of Na2CO3 with Ca(OH)2.
what is the function of caustic soda ?Caustic soda means an alkali salt or Lye, which is the common name of sodium hydroxide due corrosive nature of this salt on animal and plant tissues.
It is used in a wide range of applications and the chemical formula of sodium hydroxide is NaOH, used as cleansing agent and also in manufacturing of washing soda.
sodium hydroxide cam also applied as the reagent in the laboratories, preparation of soda lime, used in extraction of aluminum by purifying bauxite.
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1 pc
8. Some chemicals, most often inorganic salts, in the laboratory have the nasty tendency to absorb water from the
atmosphere. This property is called hygroscopicity. Anhydrous (water-free) Cupric Perchlorate [Cu(C104)2] weighs
262.447g/mol, but after sitting on out on the benchtop absorbs water from the air and now weighs 370.540g/mol. How
many water molecules did our Cupric Perchlorate absorb?
per day of a certain industrial waste chemical arrives at a treatment plant settling pond with a volume of . is destroyed by sunlight, and once in the pond it has a half-life of . Calculate the equilibrium concentration of in the pond. Round your answer to significant digits. g
The question is incomplete, the complete question is;
49.9 g per day of a certain industrial waste chemical P arrives at a treatment plant settling pond with a volume of 300 m^3. P is destroyed by sunlight, and once in the pond it has a half-life of 3.4 h. Calculate the equilibrium concentration of P in the pond. Round your answer to 2 significant digits.
Answer:
0.034 g/m³
Explanation:
From the question, mass of industrial waste = 49.9 g
It takes 24 hours to complete a day.
Mass per hour;
Mass in = (49.9 g / day) * (1 day /24 hr )
= 2.079 g/hr
Mass out = 0
Mass leaving due to sunlight = k CA V
Half life of the industrial waste = 3.4 h
This is a first order reaction;
Hence;
k = ln2/t1/2
Where, t1/2 = half life
k = 0.693 / 3.4 = 0.2038 hr⁻¹
Mass leaving due to sunlight = k CA V
CA = Mass per hr / kV
= 2.079 g/hr / ( 0.2038 hr⁻¹ x 300 m³ )
= 0.034 g/m³
which type of chemical bond would be formed between two elements having electron configuration of 1s2 2s2 2p6 3s2 and 1s2 2s2 2p4
A sample of oxygen is subjected to an absolute pressure of 2.4 atm. If the specific internal energy of the sample at 310 K is 5700 J/mol relative to a known reference state, what is the specific enthalpy of the oxygen relative to that same reference state?
Answer:
The required specific enthalpy for oxygen = 8277.34 J/mol
Explanation:
Given that :
Pressure = 2.4 atm
Temperature = 310 K
specific internal energy U = 5700 J/mol
To find the specific enthalpy using the formula:
H = U + PV
where;
H is known as the specific enthalpy
Recall that from ideal gas equation
PV = nRT
For specific enthalpy, it is constant that n = 1
Thus;
PV = RT
replacing that into the equation (H = U + PV), we have:
here;
R = 8.314 J/mol K (constant)
H = U + RT
H = 5700 J/mol +( 8.314 J/mol K × 310 K)
H = 5700 J/mol + ( 2577.34 J/mol)
H = 8277.34 J/mol
NCl3 + 3H20 - NH3 + 3HCIO
How many grams of ammonia can be produced from 1.33 grams of nitrogen trichloride?
Answer:
0.189 g
Explanation:
Step 1: Write the balanced equation
NCl₃ + 3 H₂O ⇒ NH₃ + 3 HCIO
Step 2: Calculate the moles corresponding to 1.33 g of NCl₃
The molar mass of NCl₃ is 120.36 g/mol.
1.33 g × 1 mol/120.36 g = 0.0111 mol
Step 3: Calculate the moles of NH₃ produced from 0.0111 moles of NCl₃
The molar ratio of NCl₃ to NH₃ is 1:1. The moles of NH₃ produced are 1/1 × 0.0111 mol = 0.0111 mol.
Step 4: Calculate the mass corresponding to 0.0111 moles of NH₃
The molar mass of NH₃ is 17.03 g/mol.
0.0111 mol × 17.03 g/mol = 0.189 g
Collision theory states that as molecules or ions bump into each other, a reaction will only occur if the collision has the correct amount of energy and impact is at the right angle and location. Describe how collision theory helps predict how temperature, pressure, and concentration impact reaction rates. Question 5 of 11 Collision theory states that as molecules or ions bump into each other, a reaction will only occur if the collision has the correct amount of energy and impact is at the right angle and location. Describe how collision theory helps predict how temperature, pressure, and concentration impact reaction rates. As temperature increases, the number of collisions _______ and the energy of the collisions _______.
Answer: As temperature increases, the number of collisions increases and the energy of the collisions increases.
Explanation:
According to collision theory, for a reaction to take place it is necessary to have collisions between the reacting species or atoms.
A collision will only be effective if species coming together have a certain minimum value of internal energy equal to the activation energy of the reaction.
More is the number of collisions taking place in a chemical reaction more will be the kinetic energy of its molecules. As kinetic energy is the energy acquired due to motion of atoms or a substance.
Also, collisions increases with increase in temperature as:
[tex]K.E = \frac{3}{2}kT[/tex]
Kinetic energy is directly proportional to temperature. So, more is the temperature more will be energy of molecules.
Thus, we can conclude that as temperature increases, the number of collisions increases and the energy of the collisions increases.
Question 26 (1 point)
What is the number of electrons shared between the atoms
in an 12 molecule?
Оа
7
Ob
2.
Ос
8
Od
4
Question 27 1 point)
Answer:
obviously 2 is the answer
6. What is the total number of valence electrons in an
atom of germanium in the ground state?
Answer:
4⁺
Explanation:
Germanium (Ge) has an atomic number of 32 and belongs to group 14 on the periodic table. Germanium has an electronic configuration of [Ar] 3d¹⁰ 4s² 4p². There exist 32 electrons in its neutral atom. In fluorescent lights, germanium is utilized as a component of both alloys and phosphorus.
The electrons in the atom's outer shell are known as its valence electrons.
Thus, at the ground state, the outer shell of the Germanium atom has 4 electrons.
Aerobic respiration is the cellular process in which
A)
oxygen is added to citric acid, providing energy to the cell.
B)
oxygen is added to NAD+ to form NADH.
C)
oxygen is added to an organic fuel, providing energy to the cell.
D)
oxygen is added to ATP, providing energy to the cell.
Answer:
oxygen is add to ATP providing energy to the cell
The reaction of iron (III) oxide with carbon monoxide produces iron and carbon dioxide.
Fe,O3(s) + 3CO(g) - 2Fe(s) + 3C0 (9)
If you have 39.5g of Fe2O3, how many grams of CO are required for a complete reaction?
Answer:
21g
Explanation:
no.ofmol fe2o3=39.5/(56×2+16×3)=0.25mol
from equation 1mole fe2o3 react with 3mole co
so,0.25mol fe2o3 react with 0.75mol co
mass of co=0.75×(12+16)=21g
Answer:
Approximately [tex]20.8\; \rm g[/tex].
Explanation:
[tex]\rm Fe_2O_3 \, (s) + 3\; CO\, (g) \to 2\; Fe\, (s) + 3\; CO_2\, (g)[/tex].
Relative atomic mass:
[tex]\rm Fe[/tex]: [tex]55.845[/tex].[tex]\rm C[/tex]: [tex]12.011[/tex].[tex]\rm O[/tex]: [tex]15.999[/tex].Formula mass:
[tex]\begin{aligned}M({\rm Fe_2O_3}) &= 2 \times 55.845 + 3 \times 15.999\\ &= 159.687\; \rm g \cdot mol^{-1}\end{aligned}[/tex].
[tex]\begin{aligned}M({\rm CO}) &= 12.011 + 15.999\\ &= 28.010\; \rm g \cdot mol^{-1}\end{aligned}[/tex].
Number of moles of [tex]\rm Fe_2O_3[/tex] formula units in [tex]39.5\; \rm g[/tex] of this compound:
[tex]\begin{aligned}&n({\rm Fe_2O_3}) \\ &= \frac{m({\rm Fe_2O_3})}{M({\rm Fe_2O_3})} \\ &= \frac{39.5\; \rm g}{159.687\; \rm g \cdot mol^{-1}}\approx 0.247\; \rm mol\end{aligned}[/tex].
Refer to the balanced equation for this reaction.
Coefficient of [tex]\rm Fe_2O_3[/tex]: [tex]1[/tex].Coefficient of [tex]\rm CO[/tex]: [tex]3[/tex].Hence, for every formula unit of [tex]\rm Fe_2O_3[/tex] that this reaction consumes, [tex]3\; \rm mol[/tex] of [tex]\rm CO[/tex] molecules would also need to be consumed. Therefore, if neither reactant is in excess:
[tex]\displaystyle \frac{n({\rm CO})}{n({\rm Fe_2O_3})} = \frac{3}{1} = 3[/tex].
Calculate the number of moles of [tex]\rm CO[/tex] required to react with that [tex]39.5\; \rm g[/tex] of [tex]\rm Fe_2O_3[/tex]:
[tex]\begin{aligned}&n({\rm CO}) \\ &= n({\rm Fe_2O_3}) \cdot \frac{n({\rm CO})}{n({\rm Fe_2O_3})} \\[0.5em] &\approx 0.247\; \rm mol \times 3 \approx 0.742\; \rm mol\end{aligned}[/tex].
Make use of the formula mass of [tex]\!\rm CO[/tex] to find the mass of that [tex]0.742\; \rm mol[/tex] of [tex]\rm CO[/tex] molecules:
[tex]\begin{aligned} m({\rm CO}) &= n({\rm CO}) \cdot M({\rm CO}) \\ &\approx 0.742\; \rm mol \times 28.010\; \rm g \cdot mol^{-1} \\ &\approx 20.8\; \rm g\end{aligned}[/tex].
what is work and state the law of conservation mass?
Answer:
Work is a force causing the movement or displacement of an object
law of conservation mass:
1. Atoms cannot be created or destroyed in a chemical reaction.
2. Molecules cannot be created or destroyed in a chemical reaction.
3. Compounds cannot be created or destroyed in a chemical reaction.
4. Heat cannot be created or destroyed in a chemical reaction.