Question

Calculate the number of molecules hydrogen gas consumed when 10.5 grams of HCIare producedH (9) + CI (9) HCl(9)​

a) 2.68×10²3 molecules
b) 6.02×10²3 molecules
c) 3.01×10²3 molecules
d) 1.34×10²3 molecules

Answer 1

According to the balanced equation, 2 moles of HCl are produced for every 1 mole of H₂. Convert the mass of HCl to moles using the molar mass of HCl (36.5 g/mol). The number of molecules of H₂ consumed can be calculated by multiplying the number of moles of HCl by 2 and then multiplying by Avogadro's number.

Step-by-step explanation:

According to the balanced equation, 2 moles of HCI are produced for every 1 mole of the two reactants. Therefore the number of moles of HCl produced will be twice the number of moles of H2 consumed.

First, convert the mass of solute to moles using the molar mass of HCl (36.5 g/mol):

10.5 g HCl × (1 mol HCl/36.5 g HCl) = 0.287 mol HCl

Finally, multiply the number of moles of HCl by 2 to get the number of moles of H2 consumed:

0.287 mol HCl × 2 = 0.574 mol H2

Since one mole of any substance contains 6.02 × 10^23 molecules, we can convert the number of moles of H2 to the number of molecules:

0.574 mol H2 × (6.02 × 10^23 molecules/mol) = 3.45 × 10^23 molecules

Answer: The number of molecules of hydrogen gas consumed when 10.5 grams of HCl are produced is approximately 3.45 × 10^23 molecules (Option a).