Find the mass of oxygen contained in 1 kg of potassium nitrate (KNO₃)

a) 475.5g b) 485.5g c) 475.3g d) 485.2g

formula unit mass of KNO3 = 39+14+48=   101g

In 101 g of KNO3, there are 48 g of oxygen

so in 1000g of KNO3, there will be 48/101 *1000 g of oxygen

                                                                =475.24g of oxygen