How much potassium nitrate do i need to make 21g of nitric acid?

It takes 0.333 mol (33.7 g) of KNO₃ to make 21 g of HNO₃.

KNO₃ reacts with concentrated H₂SO₄ to produce HNO₃ and KHSO₄.

(balanced.)

Each mole formula unit of KNO₃ reacts with excess H₂SO₄ to produce one mole of HNO₃. In other words, it takes the same number formula units of KNO₃ to produce a certain number of moles of HNO₃.

How many moles of molecules in 21 g of HNO₃?

Relative atomic mass:

Molar mass of HNO₃: .

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It takes 0.333 moles formula units of KNO₃ to produce 21 g or 0.333 moles of HNO₃.

What's the mass of 0.333 moles formula units of KNO₃?

Molar mass of KNO₃:

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the correct answer to this question is 2