How do the products and reactants of a chemical change compare?
a) the mass of the products is greater than the mass of the reactants because energy is taken in by the reaction.
b) the mass of the products equals the mass of the reactants because the same matter is present.
c) the mass of the products equals the mass of the reactants because there is no energy involved in the reaction.
d) the mass of the products is less than the mass of the reactants because energy is given off by the reaction.

The law of conservation of mass states that mass in an isolated system is neither created nor destroyed but transformed from one type of energy to other type of energy.
So according to above explanation,
B) The mass of the products equals the mass of the reactants because the same matter is present., is the correct answer.

Explanation:

Through the science of chemistry, earth’s basic building blocks – like carbon, hydrogen and oxygen – are transformed into materials that have helped revolutionize society. Things that many of us take for granted, like clean drinking water, pasteurization and vaccines, began as breakthroughs in chemistry.

Today, the men and women of the chemistry industry are focused on the needs of tomorrow. They are working with experts in other business sectors, at universities and in government, to develop new ways that chemistry can enable sustainability in every aspect of our lives.