Mg + 2HCl → MgCl2 + H2 How many grams of hydrochloric acid (HCI) is needed to produce 200g of H2?

7242.1g

Explanation:

The balanced equation for this reaction is as follows:

Mg + 2HCl → MgCl2 + H2

From the above equation, it can be observed that 2 moles of HCl is needed to produce 1 mole of H2.

Using the formula below, we convert the mass of H2 to moles;

Molar mass of H2 = 2.016g/mol

mole = 200/2.016

mole = 99.21mol of H2

Since 2 moles of HCl is needed to produce 1 mole of H2.

Then 99.21 moles of H2 will be produced by 99.21 × 2 = 198.4mol of HCl

Molar mass of HCl = 1 + 35.5

= 36.5g/mol

Mole = mass/molar mass

Mass = molar mass × mole

Mass = 36.5 × 198.4

Mass = 7242.1g

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