Answer:
Within three molecules of Ethane, it would have 6 carbon, and 18 hydrogen atoms in it.
Explanation:
A 52.9g sample of brass, which has a specific heat capacity of 0.375·J·g^−1°C^−1, is put into a calorimeter (see sketch at right) that contains 100.0g of water. The temperature of the water starts off at 15.0°C. When the temperature of the water stops changing it's 18.4°C. The pressure remains constant at 1 atm. Calculate the initial temperature of the brass sample.
Answer: 90.04°C
Explanation: Calorimeter is a device measures the amount of heat of a chemical or physical process. An ideal calorimeter is one that is well-insulated, i.e., prevent the transfer of heat between the calorimeter and its surroundings. So, the net heat change inside the calorimeter is zero:
[tex]q_{1}+q_{2}=0[/tex]
Rearraging, it can be written as
[tex]q_{1}=-q_{2}[/tex]
showing that the heat gained by Substance 1 is equal to the energy lost by Substance 2.
In our case, water is gaining heat, because its temperature has risen and so, brass is losing energy:
[tex]q_{water}=-q_{brass}[/tex]
Calculating:
[tex]m_{w}.c_{w}.\Delta T=-[m_{b}.c_{b}.\Delta T][/tex]
[tex]100.4.18.(18.4-15)=-[52.9.0.375.(18.4-T)][/tex]
Note: final temperature is the same as the substances are in thermal equilibrium.
Solving:
418(3.4)= - 365.01 + 19.8375T
19.8375T = 1786.21
T = 90.04
The initial temperature for the sample of brass was 90.04°.
Quartz,SiO2,contains 46.7% silicon. What mass of silicon is present in 381 g of quartz?
Answer:
119 g.
Explanation:
Determine the entropy change for the combustion of gaseous propane, C3H8, under standard state conditions to give gaseous carbon dioxide and water.
Answer:
ΔS°reaction = 100.9 J K⁻¹ (mol C₃H₈)⁻¹
Explanation:
The equation for the reaction is given as;
C₃H₈(g) + 5O₂(g) → 4H₂O(g) + 3CO₂(g)
In order to determine the entropy change, we have to use the entropy valuues for the species in the reaction. This is given as;
S°[C₃H₈(g)] = 269.9 J K⁻¹ mol⁻¹
S°[O₂(g)] = 205.1 J K⁻¹ mol⁻¹
S°[H₂O(g)] = 188.8 J K⁻¹ mol⁻¹
S°[CO₂(g)] = 213.7 J K⁻¹ mol⁻¹
The unit of entropy is J K⁻¹ mol⁻¹
Entropy change for the reaction is given as;
ΔS°reaction = ΔS°product - ΔS°reactant
ΔS°reaction = [(4 * 188.8) + (3 * 213.7)] - [269.9 + (5 * 205.1)]
ΔS°reaction = 100.9 J K⁻¹ (mol C₃H₈)⁻¹
The entropy change for the combustion of gaseous propane, under standard state conditions 100.9 J K⁻¹.
The equation for the combustion of gaseous propane is given as follows:-
C₃H₈(g) + 5O₂(g) → 4H₂O(g) + 3CO₂(g)
In order to determine the entropy change, we have to use the entropy values for the species in the reaction. This is as follows:-
S°[C₃H₈(g)] = 269.9 J K⁻¹ mol⁻¹
S°[O₂(g)] = 205.1 J K⁻¹ mol⁻¹
S°[H₂O(g)] = 188.8 J K⁻¹ mol⁻¹
S°[CO₂(g)] = 213.7 J K⁻¹ mol⁻¹
The unit of entropy is J K⁻¹ mol⁻¹
Entropy change for the reaction is given as;
ΔS°reaction =nproduct ΔS°product - nreactantΔS°reactant
ΔS°reaction = [(4mol * 188.8 J K⁻¹ mol⁻¹) + (3 mol * 213.7 J K⁻¹ mol⁻¹)] - [(1 mol*269.9J K⁻¹ mol⁻¹ )+ (5 mol* 205.1 J K⁻¹ mol⁻¹)]
ΔS°reaction = 100.9 J K⁻¹
So, the entropy change for the combustion of gaseous propane is 100.9 J K⁻¹ .
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What is the voltage in a circuit is the current is 3 amps and the resistance is 3 ohms
Answer:
9
Explanation:
V=I*R
3*3
Thats the answer
How can people conserve water at home?
Answer:
Turning off the water while brushing teeth, watching shower time.
Explanation:
Answer:
Take shorter showers.
Install water-saving shower heads or flow restrictors.
Turn off the water while brushing your teeth.
Turn off the water while shaving.
Explanation:
have a nice day
I’m stuck on this can I get a little help please
Answer:
table A
Explanation:
its table A because it requires less force push. the less force used the less friction there is.
the less friction there is the more smooth a surface is.
Consider the elementary gas-phase reversible reaction A 3C Pure A enters at a temperature of 400 K and a pressure of 10 atm. At this temperature, KC 0.25(mol/dm3)2. Calculate the equilibrium conversion for each of the following situations: (a) The gas-phase reaction is carried out in a constant-volume batch reactor. (b) The gas-phase reaction is carried out in a constant-pressure batch reactor. (c) Can you explain the reason why there would be a difference in the two values of the equilibrium conversion
Answer:
a) Xac = 0.39
b) Xac = 0.58
c) There would be a difference in the two values of the equilibrium conversion because in constant pressure condition it would take longer time to reach the same conversion rate ( higher conversion equilibrium ) and this because the volume increase with the reaction at constant pressure
Explanation:
From elementary gas phase reaction
Cao = Po / RT
Po = 10
R = 82.06
T = 400 K
Cao = 3.05 * 10^-4 mol/cm^3 ≈ 0.305 mol/dm^3
Kc = 0.25 (mol/dm^3 )^2
Calculate the equilibrium conversion for each of the following situations
a) The gas-phase reaction is carried out in a constant-volume batch reactor
Xac = 0.39
b) The gas-phase reaction is carried out in a constant-pressure batch reactor
Xac = 0.58
c) There would be a difference in the two values of the equilibrium conversion because in constant pressure condition it would take longer time to reach the same conversion rate ( higher conversion equilibrium ) and this because the volume increase with the reaction at constant pressure
Attached below is a detailed solution as regards the question above
Select the statement that best describes components of complete and incomplete metamorphosis. (2 points)
a. During incomplete metamorphosis, the nymph molts its exoskeleton. During complete metamorphosis, the larva forms a chrysalis or cocoon.
Selected:b. During incomplete metamorphosis, the pupa molts its exoskeleton. During complete metamorphosis, the nymph wraps itself in a chrysalis.This answer is incorrect.
c. Incomplete and complete metamorphosis both have four major stages.
d. Incomplete and complete metamorphosis both have three major stages. btw b was wrong
Answer:
a. During incomplete metamorphosis, the nymph molts its exoskeleton. During complete metamorphosis, the larva forms a chrysalis or cocoon.
Explanation:
The first stage of incomplete metamorphosis is the egg. During this time, the insect will hatch into a form called a nymph. The nymph is basically a small version of the adult insect. This is very similar to how a child looks like his or her parents.
The correct statement that describes components of complete and incomplete metamorphosis is: d. Incomplete and complete metamorphosis both have three major stages.
What is metamorphosis ?Metamorphosis is a biological process that some animals undergo to transform from one developmental stage to another, typically from a juvenile form to an adult form. This process involves a series of physical and physiological changes that can be dramatic and even complete.
Incomplete metamorphosis consists of three stages: egg, nymph, and adult. The nymph hatches from the egg and looks similar to the adult but lacks wings and reproductive organs. The nymph molts its exoskeleton several times and gradually develops into an adult.
Complete metamorphosis also consists of three stages: egg, larva, pupa, and adult. The larva hatches from the egg and looks completely different from the adult, often worm-like in appearance. The larva undergoes a series of molts and grows larger, then forms a pupa or chrysalis. Inside the pupa or chrysalis, the larva undergoes a complete transformation and emerges as an adult.
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Perform the following
mathematical operation, and
report the answer to the
appropriate number of
significant figures.
653.12 + 12.10247 = [?
Answer:
665.22
Explanation:
you see wich numbers after the decimal points have the least numbers, the one with the least u have to round your answer to that
After performing the required mathematical operation (addition), the answer is equal to 665.22.
What are significant figures?In Mathematics, significant figures can be defined as the number of single digits or numerical values in the coefficient of a mathematical expression that are important and meaningful.
Since "653.12" has two (2) significant figures, we must ensure that 12.10247 also has two (2) significant figures as follows:
12.10247 to 2 S.F = 12.10.
Next, we would perform the required mathematical operation (addition):
653.12 + 12.10 = 665.22.
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Number of atoms in 4.26 moles of (NH4)3PO4
Answer:
20 atoms
Explanation:
n=3
H =12
p=1
O=4
3+12+1+4=20
Why are cars manufactures exploring hydrogen fuel cell technology as a possiable replacement for gasoline burning engines
5. Write the two resonance hybrids for the carbocation that would be formed by protonation at C-1 of 2-methyl-1,3-pentadiene. Without doing a calculation, would you expect C-2 or C-4 (the two end carbons of the allylic cation) to have the most positive charge on it
Answer:
Follows are the solution to this question:
Explanation:
Please find the complete solution in the attached file.
what is the molar mass of Disodium sulfide nonahydrate
(Compound)
I'm confused about the number of moles per element
Answer:
240 g/mol
Explanation:
We'll begin by writing the chemical formula of Disodium sulfide nonahydrate. This is illustrated below:
The molecular formula of disodium sulfide nonahydrate is Na₂S.9H₂O
Finally, we shall determine the molar mass of disodium sulfide nonahydrate, Na₂S.9H₂O. This can be obtained by adding the individual molar mass of the element present in the compound as illustrated below:
Molar mass of Na₂S.9H₂O = (23×2) + 32 + 9[(2×1) + 16]
= 46 + 32 + 9[2 + 16]
= 46 + 32 + 9[18]
= 46 + 32 + 162
= 240 g/mol
Thus, the molar mass of disodium sulfide nonahydrate, Na₂S.9H₂O is 240 g/mol
which explains how coolers work?
Answer:
Forgive me if im wrong but i am pretty sure the answer is C
Explanation:
What is limited reactant?
Answer:
The limiting reagent is the reactant that is used up completely. This stops the reaction and no further products are made. ... The limiting reagent can also be derived by comparing the amount of products that can be formed from each reactant.
Answer:
The limiting reagent is the reactant that is used up completely. This stops the reaction and no further products are made. ... The limiting reagent can also be derived by comparing the amount of products that can be formed from each reactant.
Explanation:
Disclaimer not my answer I looked it up
What volume (mL) of 0.250 M HNO3 is required to titrate (neutralize) a solution containing 0.276 g of KOH?
Answer:
Volume = 19.68 ml
Explanation:
The equation of the reaction is given as;
HNO3 + KOH ---> KNO3 + H2O
1 mol of HNO3 reacts 1 mol of KOH
Converting 0.276 g of KOH to mol;
Number of moles = Mass / Molar mass
Number of moles = 0.276g / 56.1056 g/mol
Number of moles = 0.00492
Since the mole relationship is 1 = 1;
This means 0.00492 mol of HNO3 reacts with 0.00492 mol of KOH
The relationship between molarity and volume id given as;
Molarity = Number of moles / Volume
Volume = Number of moles / Molarity = 0.00492 mol / 0.250 M
Volume = 0.01968 L
Volume = 19.68 ml
Where did the magma and sediment that formed the rock of the Great Plains and the Rocky
Mountains come from?
Which claim do you think is more likely to be true?
Claim 1: The sediment that formed the Great Plains came from the rock of the Rocky
Mountains.
Claim 2: The magma that formed the Rocky Mountains came from the rock of the Great Plains.
Answer:
1
Explanation seems right
The magma and sediments formed in the great plains are came from the rocks of the rocky mountains. Therefore, claim 1 is correct.
What is sedimentation?Sedimentation is the geographical process of accumulation or deposition of the minerals and organic particles from the earth's surface is called sedimentation. This process results in the formation of sedimentary rocks.
Weathering or erosion of rocks by wind, water or other chemicals leads to the geological debris which then move to other places deposits somewhere.
Rocks in the rocky mountains undergo erosion and the mass movements created by wind or water leads to the sedimentation of these rocky solids to other places. The rocks in the Great planes are reached there by the mass movement of the rocks of rocky mountains. Hence, claim 1 is correct.
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Can you guys help me explain these? I will mark brainliest to whoever answers it right oh and this is due tommorow so im rushing!
Answer:
Conduction
Conduction moves heat through direct sub-atomic crash. A region of more prominent dynamic energy will move nuclear power to a region with lower active energy. Higher-speed particles will crash into more slow speed particles. The more slow speed particles will increment in motor energy subsequently. Conduction is the most widely recognized type of warmth move and happens through actual contact. Models is place your hand against a window or spot metal into an open fire.
The interaction of warmth conduction relies upon the accompanying components: temperature slope, cross-segment of the material, length of the movement was, and actual material properties. The temperature inclination is the actual amount that portrays the bearing and pace of warmth travel. Temperature stream will consistently happen from most sultry to coldest or, as expressed previously, higher to bring down active energy. Once there's warm harmony between the two temperature contrasts, the warm exchange stops.
Convection
At the point when a liquid, like air or a fluid, is warmed and afterward ventures from the source, it conveys the nuclear power along. This sort of warmth move is called convection. The liquid over a hot surface grows, turns out to be less thick, and rises.
Radiation
Thermal radiation generates from the emission of electromagnetic waves. These waves carry the energy away from the emitting object. Radiation occurs through a vacuum or any transparent medium (either solid or fluid). Thermal radiation is the direct result of random movements of atoms and molecules in matter. Movement of the charged protons and electrons results in the emission of electromagnetic radiation.
Suppose you wanted to cause Pb2+ ions to come out of solution as solid Pb. Which metal(s) could you use to accomplish this? Au Zn Ca Ni Ag AlFe
Answer:
Ca, Zn, Ni, Al, Fe
Explanation:
The activity series is an arrangement of metals in order of decreasing reactivity.
Metals that are high up in the activity series are very reactive. They displace metals that are lower in the activity series from an aqueous solution of their salts.
The metals; Ca, Zn, Ni, Al, Fe are all above Pb in the activity series hence they will cause Pb2+ ions to come out of solution as solid Pb.
A more reactive metal displaces the less reactive metals in the solution. Ca, Al, Zn, and Fe can be accomplished to take out the [tex]\bold{ Pb^2^+}[/tex] from the solution as solid Pb.
Metal displacement Reaction:
In this type of reaction a more reactive metal displaces the less reactive metals in the solution.
The metal reactivity series
Ca > Al > Zn > Fe > Ni > Pb > Ag > Au
The lead ( Pb) is less reactive than the Ca, Al, Zn, and Fe.
Therefore, Ca, Al, Zn, and Fe can be accomplished to take out the [tex]\bold{ Pb^2^+}[/tex] from the solution as solid Pb.
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The dissociation constant of formic acid and acetic acid are 2.14×10^-4 and 1.81×10^-5 respectively. What is the relative strength of the acids
Answer: The formic acid is 3.5 times stronger than acetic acid.
Explanation:
The strength of an acid depends on its acid dissociation constant.
For a hypothetical monoprotic acid HA, the dissociation equilibrium is:
[tex]HA\rightleftharpoons H^++A^-[/tex]
[tex]K_a=\frac{[H^+][A^-]}{[HA]}[/tex]
More is the value of [tex]K_a[/tex] , greater is the dissociation and stronger is the acid.
[tex]\frac{Strength_{\text {formic acid}}}{Strength_{\text {acetic acid}}}=\sqrt{\frac{2.14\times 10^{-4}}{1.81\times 10^{-5}}}=3.5[/tex]
Thus formic acid is 3.5 times stronger than acetic acid.
Can you guys please help me I will mark brainliest to whoever answers this right.
the tense..........used to describe events that have not yet taken place
Answer:
Future tense.
Explanation:
The different tenses in grammar are used to denote the time or condition of when the action occurs. This means that tenses tell us the form or condition of the verbs.
The present tense tells us about a present scene while the past tense tells us about an action that happened in the past. Likewise, the future tense tells us about an event that will happen in the future. This means that future tenses are used to describe events that have not taken place, and are yet to happen.
Answering the following questions will help you focus on the outcomes of the experiments.
Experiment 1:
1. What happens to the water in the small tube as the water in the test tube absorbs heat?
2. Why do you think a small tube was used to observe the expansion of water?
Experiment 2:
1. Compare the circumference of the balloon before and after freezing. What is the percent increase in this
measurement?
Combined Results
Write a summary paragraph discussing this experiment and the results. Use the following questions and topics to help
guide the content of your paragraph.
Summarize the conclusions that you can draw from this experiment. Use the questions above to guide your ideas.
2. Summarize any difficulties or problems you had in performing the experiment that might have affected the results.
Describe how you might change the procedure to avoid these problems.
3. Describe at least two real-world issues or examples that illustrate the findings of this experiment.
WRITER
Word Count: of 400
OVERALL SCORE:
Answer:
ex.1
1.The water in the test tube expands as it is heated. There is only one direction to expand in, the glass tube. This glass tube is narrow so that a small change in volume will result in a considerable change in height; your signal is amplified. This is the same phenomenon as in thermometers with a glass bulb on the lower end.
2. there will be a thermal expansion will happened.
Heart attacks can cause sudden death.
True
False
Answer:
True
Explanation:
An aqueous solution of sodium hydroxide is standardized by titration with a 0.104 M solution of hydrobromic acid. If 13.5 mL of base are required to neutralize 20.2 mL of the acid, what is the molarity of the sodium hydroxide solution?
Answer:
0.156 M
Explanation:
The neutralization reaction between hydrobromic acid (HBr) and sodium hydroxide (NaOH) is the following:
HBr(ac) + NaOH(aq) → NaBr(aq) + H₂O(l)
As we can see, 1 mol of HBr reacts with 1 mol NaOH. During a titration, at the equivalence point, the number of moles of NaOH added reacts completely with the number of moles of HBr:
moles of NaOH = moles of HBr
The moles of each reactant is calculated as the product of the molarity (M) and the volume (V):
M(NaOH) x V(NaOH) = M(HBr) x V(HBr)
We have the following data:
base: V(NaOH) = 13.5 mL
acid: M(HBr) = 0.104 M; V(HBr) = 20.2 mL
Thus, we calculate M(NaOH) from the equivalent point equation:
M(NaOH) = (M(HBr) x V(HBr))/(V(NaOH) = (0.104 M x 20.2 mL)/(13.5 mL) = 0.1556 M ≅ 0.156 M
Which of the following statements correctly explain the relationship between the solubility of a gas and its pressure?
A. As pressure is increased, the rate at which gas molecules enter the solution decreases.
B. More gas molecules are soluble as pressure is increased.
C. The solubility of a gas decreases with a decrease in pressure.
D. The solubility of nitrogen gas at 2.00 atmatm is twice the solubility of the gas at 1.00 atmatm.
E. The concentration of gas particles in the solution is higher at 4.25 atmatm than at 1.00 atmatm.
F. Fewer gas molecules are soluble at higher pressures.
G. As pressure decreases, the concentration of gas molecules in the solution increases.
Answer:
B, C, D, E
Explanation:
According to Henry's law, as the pressure is increased, the solubility of a given gas increases. So, solubility is directly proportional to pressure.
Thus, the following statements are correct:
B. More gas molecules are soluble as pressure is increased.
Is correct because as the pressure is increased, the solubility increases.
C. The solubility of a gas decreases with a decrease in pressure.
Is correct because solubility and pressure are directly proportional: if the pressure is decreased, the solubility will be decreased.
D. The solubility of nitrogen gas at 2.00 atm is twice the solubility of the gas at 1.00 atm.
Is correct because 2.00 atm is twice 1.00 atm, so if the pressure is increased twice, the solubility is increased twice.
E. The concentration of gas particles in the solution is higher at 4.25 atm than at 1.00 atm.
Is correct because 4.25 atm>1.00 atm (the higher the pressure, the higher the solubility, and therefore the concentration of gas particles in solution).
The remaining options (A, G) are incorrect. They contradict Henry's law.
PLEASE HELP PLEASE HELP PLEASE HELP PLEASE HELP PLEASE HELP PLEASE HELP PLEASE HELP PLEASE HELP PLEASE HELP PLEWSE HELP PLEASE HELP ANYBODY!!! CHEMISTRY DUE IN 5 MINUTES!! DIMENSIONAL ANALYSIS
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?
WILL GIVE BRAINLIEST PLEASE ANYONE WHO KNOWS HOW TO DO MOLE CONVERSIONS AND DIMENSIONAL ANALYSIS
Answer:
23.6 moles
Explanation:
From the question given above, the following data were obtained:
Mass of air = 3.6 Kg
Mass percentage of O₂ = 21%
Number of mole of O₂ =?
Next, we shall convert 3.6 Kg of air to grams (g). This can be obtained as follow:
1 kg = 1000 g
Therefore,
3.6 Kg = 3.6 Kg × 1000 / 1 kg
3.6 Kg = 3600 g
Next, we shall determine the mass of O₂ in the air. This can be obtained as follow:
Mass of air = 3600 g
Mass percentage of O₂ = 21%
Mass of O₂ =?
Mass of O₂ = 21% × 3600
Mass of O₂ = 21/100 × 3600
Mass of O₂ = 756 g
Finally, we shall determine the number of mole of O₂ in the sample of air. This can be obtained as follow:
Mass of O₂ = 756 g
Molar mass of O₂ = 2 × 16 = 32 g/mol
Number of mole of O₂ =?
Mole = mass /Molar mass
Number of mole of O₂ = 756 / 32
Number of mole of O₂ = 23.6 moles
Thus, the number of mole of O₂ in the
sample of air is 23.6 moles
1. How many molecules are in 4.5 moles?
Answer:
depends on what molecule you are looking for
Explanation:
In one mole of stuff (atoms, molecules, eggses), there are NA individual items of that stuff. So, there are 4.5 × NA BCl3 molecules; i.e. 4.5 × 6.022×1023 ≅ 27×1023 individual molecules of BCl3
A) Suppose you separate a 3.02 g mixture of sand and salt. You recover 1.43 g of salt and 1.41 g of sand. What is the percent recovery of the mixture?
B) Suppose you separate a 3.02 g mixture of sand and salt. You recover 1.43 g of salt and 1.41 g of sand. What is the percent recovery of the mixture?
C) Calculate the percent by mass of a solution made from 15 g NaCl (the solute) and 69 g water.
D) What percent of 73.0 g is 26.1 g?
Answer:
A-B) 94 %.
C) 17.9 %.
D) 35.8 %.
Explanation:
Hello!
A-B) In this case, since the total mass of the mixture is 3.02 g and 1.43g+1.41g=2.84 g are recovered in total, we can compute the percent recovery as shown below:
[tex]\%rec=\frac{2.84g}{3.02g}*100\%\\\\\%rec=94\%[/tex]
C) Here, since the solution is made up of NaCl and water, we can say that the mass of the solution is 15g+69g=84g; thus, the percent by mass would be:
[tex]\%=\frac{15g}{84g}*100\%\\\\\%=17.9\%[/tex]
D) In this case, we simply divide 26.1 g by 73.0 g in order to obtain the percent:
[tex]\%=\frac{26.1g}{73.0g}*100\%\\\\\%=35.8\%[/tex]
Best regards!
The percentage in the cases are as follows;
A and B is; 94%C is; 17.9%D is; 35.8%Questions A and B are similar and can be solved as follows;
The total mass of the mixture is 3.02g.The recovered mass = 1.43g + 1.41g = 2.84g% recovery = (2.84/3.02) × 100%% recovery = 94%Question C can be solved as follows;
Total mass of solution = 15 + 69 = 84gMass of solute = 15g% by mass = (15/84) × 100%% by mass = 17.9%Question D can be solved as follows;
% = (26.1/73) × 100%% = 35.8%Read more:
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Ammonia reacts with oxygen to form nitrogen dioxide and water according to the
following equation:
4NH71875) + 70212) ---> 4NO2/2) + 6H2013)
You react ammonia and oxygen, and at the end of the experiment you find that you
produced 23 g of water and have 8.52 g of ammonia left over. Determine the mass of
oxygen reacted.
17.66 g 02
40.85 g 02
O 47.66 g 02
71.49 g 02
35.02 g 02
B