Answer:
1. C. helium
2. D. oxygen and acetylene
3. B. deliquescence
4. C. cutting very hard surfaces
5. B. 3.5%
Explanation:
Answer:
No limiting reagent. There is an exact amount of each.
Explanation:
Start by getting the equation
Fe + O2 -> Fe2O3
If you balance the oxygens the Fe will easily follow.
Fe + 3O2 => 2Fe2O3
So far what you have is 6 oxygens on the right and 6 on the left. Now all you need do is balance the irons. The are 4 on the right (2Fe2). So you must have 4 on the left.
4Fe + 3O2 -> 2Fe2O3
Now to your question if you have 4 mols of iron, you need 3 mols of O2. Those are the balance numbers of the equation. They also represent mols.
There is no limiting reagent in the theoretical world of chemistry. All the iron will be used up and so will the given amount of oxygen.
The heterogeneous mixture that has very small dispersed particles and stays mixed for a long time is colloid. Because colloid has particles that are small enough to suspended but are as large that they can scatter light.
<span>Balance the equation
8Zn + S8 -----> 8ZnS
work out how much ZnS is possible if all of each reagent were to react. The reagent that produces the least product is the limiting reagent.
moles Zn = mass / molar mass = 4.88 g / 65.38 g/mol = 0.07464 moles
8 moles Zn reacts to form 8 moles ZnS
Therefore moles ZnS possible = moles Zn = 0.07464 moles
moles S8 = 5.03 g / 256.48 g/mol = 0.01961 mol
1 mole S8 reacts to form 8 moles ZnS
Therefore moles ZnS possible = 8 x moles S8 = 0.1569 mol
The amount of Zn provided gives the least ZnS, therefore Zn is the limiting reagent.
The theoretical yield is the maximum possible yield possible from the reagents provided. It is the amount of product that will form if all the limiting reagent reacts.
So in this case 4.88 g Zn yields 0.07464 mol ZnS
theoretical mass ZnS = molar mass x moles
= 97.44 g/mol x 0.07464 mol
= 7.27 g
% yield = actual yield / theoretical yield x 100/1
= 6.02 g / 7.27 g x 100/1
= 82.8 %</span>
