Question

Two molecules of hydrogen react with one molecule of oxygen to produce two

Answer 1

Answer :

(1) The number of molecules of water produced are, $4.06\times 10^{23}$

(2) The number of moles of water produced are, 45 moles

Explanation :

The balanced chemical reaction will be,

$2H_2+O_2\rightarrow 2H_2O$

For 1 :

From the balanced reaction, we conclude that

As, 1 molecule of oxygen react to produces 2 molecules of water

So, $2.03\times 10^{23}$ molecule of oxygen react to produces $2\times (2.03\times 10^{23})=4.06\times 10^{23}$ molecules of water

Therefore, the number of molecules of water produced are, $4.06\times 10^{23}$

For 2 :

From the balanced reaction, we conclude that

As, 1 mole of oxygen react to produces 2 mole of water

So, 22.5 mole of oxygen react to produces $2\times 22.5=45$ moles of water

Therefore, the number of moles of water produced are, 45 moles

Answer 2

You would need to utilize Mole ratios found in the adjusted condition; 
for each mole of hydrogen utilized, 2 moles of HCl are delivered. 
Thusly: 
10 mol H2 x 2 mol HCl/1 mol H2 = 20 mol HCL. 
For the second question: 
you would need to change over 2.0x10^23 particles of Oxygen to moles of oxygen, utilizing Avogadro's number: 
2.0x10^23 particles oxygen x 1 mol oxygen/6.022x10^23 atoms oxygen = 0.33 mol Oxygen 
utilizing mole proportions once more: 
 0.66 mol H2O = 2 mol H2O/1 mol Oxygen x 0.33 mol Oxygen 
45.0 mol H2O  = 2 mol H2O/1 mol Oxygen x 22.5 mol Oxygen 
fundamentally to answer stoichiometry, you should take a gander at the adjusted condition to make sense of the mole proportions between components/mixes, and utilizing mole proportions you can change over from moles of one component/compound to moles of another component/compound