Conservation of Mass Review

Front

What are substances that react in a chemical reaction?

Back

Reactants

Front

What are substances that form as the result of a chemical reaction?

Back

Products

Front

What does the law of conservation of mass state?

Back

In a closed system, the mass of the reactants must equal the mass of the products.

Front

If the mass of reactants is 22 g and the mass of products is 20 g, what could explain this discrepancy?

Back

We might not have been able to measure all the products, for example if a gas was produced.

Front

How many oxygen atoms are in the products for the reaction: @@4Fe + 3O_{2} ightarrow 2Fe_2O_3@@?

Back

6

Front

Is the equation @@4Fe + 3O_{2} ightarrow 2Fe_2O_3@@ balanced?

Back

No

Front

What are coefficients in a chemical equation?

Back

Numbers placed before compounds to indicate the number of molecules or moles of that substance.

Front

What are subscripts in a chemical formula?

Back

Numbers written after an element to indicate the number of atoms of that element in a molecule.

Front

What is an example of a chemical reaction?

Back

Combustion of methane: @@CH_4 + 2O_2 ightarrow CO_2 + 2H_2O@@.

Front

What is the significance of balancing chemical equations?

Back

It ensures that the law of conservation of mass is upheld.