100g of calcium carbonate was heated until it decomposed to give calcium oxide and carbon dioxide. 56g of calcium oxide was left. work out the mass of carbon dioxide given off.

In water, a strong acid will break down into its component parts. a. completely b. partly c. never in water, a weak base will break down into its component parts. a. completely b. partly c. never

Which of the following is the correct definition of chemical energy? a. energy an object has because of its motion or position b. energy resulting from the flow of charged particles, such as electrons or ions c. energy produced from the splitting of atoms d. energy stored in chemical bonds of molecules

Reactions in cells take place at about a. 40°c b. 0° c. 100°c d. 60°c