(a) Quick lime: Calcium and Oxygen
(b) Hydrogen bromide: Hydrogen and Bromine
(c) Baking powder: Sodium, Hydrogen, Carbon, and Oxygen
(d) Potassium sulphate: Potassium, Sulfur, and Oxygen
Explanation:
Quick lime
is chemically known as calcium oxide (CaO), so it contains Calcium and Oxygen.
Hydrogen bromide
has the chemical formula HBr, indicating it is composed of Hydrogen and Bromine.
Baking powder
is a complex compound containing various elements, but primarily Sodium, Hydrogen, Carbon, and Oxygen.
Potassium sulfate
has the chemical formula K2SO4, meaning it contains Potassium, Sulfur, and Oxygen.