Question

Calculate the number of grams of KNO3 necessary to produce 6.90 grams of
oxygen gas.

Answer 1

first you need find number of mole

number of mole =given mass/ molar mass. 6.90g/16g/mol =0.431mol . mass =molar mass × number of mole KNO3 = 101g/mol × 0.431 mol = 43.5g .