Question

How many moles of hydrogen are in the sample?
Round your answer to 4 significant digits.

Answer 1

1.56 mol H₂

Step-by-step explanation:

Mg₃(Si₂O₅)₂(OH)₂

There are 4 Si moles per Mg₃(Si₂O₅)₂(OH)₂ mol. With that in mind we can calculate how many Mg₃(Si₂O₅)₂(OH)₂ moles are there in the sample, using the given number of silicon moles:

• 3.120 mol Si *
  `(1molMg_3(Si_2O_5)_2(OH)_2)/(4molSi)` = 0.78 mol Mg₃(Si₂O₅)₂(OH)₂

Then we can convert Mg₃(Si₂O₅)₂(OH)₂ moles into hydrogen moles, keeping in mind that there are 2 hydrogen moles per Mg₃(Si₂O₅)₂(OH)₂ mol:

• 0.78 mol Mg₃(Si₂O₅)₂(OH)₂ * 2 = 1.56 mol H₂