can someone help me please!?

Question

hi, i just need help with some chemistry problems...I've been working so hard to try to understand on how to do these problems and its just not clicking so if you could possibly answer them and explain how you do them please!!! and please use terms that a young child can understand because thats how i am when it comes to chemistry! Thanks!

1.How many grams of hydrogen are produced by the action of hydrochloric acid on 50 grams of zinc?


2.How many grams of copper oxide may be reduced by 10 grams of hydrogen?



3.How many grams of sodium chloride are required to react with 196 grams of H2SO4?


4.How many grams of mercuric oxide are needed to produce 100 liters of O2?



5.How many grams of zinc are needed to produce 100 liters of hydrogen by acid replacement?



6.How many liters of hydrogen are needed to reduce 120 grams of copper oxide?

7.How many liters of oxygen may be obtained by electrolysis of 900 grams

Answer 1

These are all essentially the same question, so I'll explain how you need to proceed and let you figure out the rest.

1. The reaction is as follows:
2HCl + 2Zn -----> H2 + 2ZnCl

Find the atomic weight of both zinc and hydrogen from the periodic table. Divide 50 by the atomic weight of Zn to determine how many moles of Zn you have, then multiply that by the atomic weight of hydrogen to get your final answer. (Note that you don't have to worry about the fact that there are 2 parts zinc reacting because hydrogen is diatomic and will therefore also be doubled.)

Answer 2

1. They give you grams of zinc. They ask for grams of hydrogen. The balanced equation is Zn + 2HCl ===> ZnCl2 + H2. Atomic weights are Zn=65, H=1. At the far right of the sheet of paper, put a "=" sign. After that, leave a space and write gH2. The number answer goes there. At the far left side of the paper, write 50g Zn. Multiply by 1 g-atom Zn/65gZn. The gZn cancel, leaving the number of g-atoms (gram atoms) of Zn. Next, multiply by 1molH2/1g-atom Zn. This comes from the balanced equation. The g-atom Zn cancel, leaving moles of H2. Next multiply by 2gH2/1mol H2. The molH2 cancel, leaving gH2, which is the desired answer. In other words:

50gZn x 1g-atomZn/65gZn x 1molH2/1g-atomZn x 2gH2/1molH2 = Answer

2. They give you 10gH2. They ask for gCuO. [Dear friend: There are two oxides of copper, CuO and Cu2O. We'll suppose CuO. I suspect we're right.] The balanced equation is CuO + H2 ===> Cu + H2O. Atomic weights are Cu=63.5, H=1. Write an "=" sign at the far right of the paper, leaving a little space to write gCuO. The number answer goes in that space. Begin with 10gH2. Multiply by 1molH2/2gH2. The gH2 cancel, leaving molH2. Multiply by 1molCuO/1molH2. That comes from the balanced equation. The molH2 cancel, leaving molCuO. Multiply by 80gCuO/1molCuO. The molCuO cancel, leaving gCuO, which is the answer. In other words,

10gH2 x 1molH2/2gH2 x 1molCuO/1molH2 x 80gCuO/1molCuO = Answer

3. This is a little hard, but let's suppose that they want complete reaction and whoosh hydrogen chloride gas off someplace. The balanced equation would be H2SO4 + 2NaCl ===> 2HCl(gas) + Na2SO4. They ask how many gNaCl to react with 196gH2SO4. Atomic weights are Na=23, Cl=35.5, H=1, S=32, O=16. So write an "=" sign at the far right, leaving a space before writing gNaCl. The number answer you will write in the space. At the left, put 196gH2SO4. Multiply by 1molH2SO4/98gH2SO4. The gH2SO4 cancel the gH2SO4, leaving molH2SO4. Multiply by 2molNaCl/1molH2SO4. This comes from the balanced equation. Next multiply by 58.5gNaCl/1molNaCl.The molNaCl cancel, leaving gNaCl, which is the answer.

4. Business as usual: Have L O2, need gHgO. The balanced equation is 2HgO ===> 2Hg + O2. Atomic weights: Hg=200, O=16. Write an "=" sign on the right end of the paper, leaving room for a space for the answer and gHgO. Write 100L O2 on the left. Multiply by 1molO2/22.4L O2.

This is new in these problems. There is 22.4L of gas per mole of a perfect gas at standard temperature and pressure (STP). This is a chemical fact that you must learn. Standard temperature is 0degC or 273degK. Standard pressure is 760mmHg or 1atm. These people do not specify, so let us suppose that they mean STP.

Anyway, the L O2 cancel the L O2, leaving the molesO2. Multiply by 2molHgO/1molO2. This comes from the balanced equation. This gives the molesHgO required. Multiply by 216gHgO/1moleHgO to get grams GO, which was the answer.

Answer 3

All problems
a) Write out balanced chemical equation
b) Convert to moles of substance you have using the molecular mass in g/mol (for volumes there is a set number of litres of a gas in 1 mol, which I believe is 22.4 L/mol).
c) Convert to moles of substance you are looking for using the stoichiometric ratios obtained from the balanced chemical equation
d) Convert to mass/volume substance you are looking for