Unit 2 Test Review Part 2

Front

What is the law of conservation of mass?

Back

The law of conservation of mass states that mass is neither created nor destroyed in a chemical reaction. The total mass of reactants equals the total mass of products.

Front

If a reaction starts with 75g of reactants, how much product should be produced?

Back

75g of products.

Front

What is the mass of a saltwater mixture if 25 grams of salt is dissolved in 1,000 grams of water?

Back

1,025 grams.

Front

What does it mean if two elements are in the same period on the periodic table?

Back

It means they have the same number of energy levels.

Front

What is a coefficient in a chemical equation?

Back

A coefficient is a number in front of a chemical formula that indicates how many molecules or atoms of each reactant and product are involved in a reaction.

Front

How can you tell if a chemical reaction is balanced?

Back

A chemical reaction is balanced if the number of atoms of each element is the same on both sides of the equation.

Front

What is a reactant in a chemical reaction?

Back

A reactant is a substance that undergoes change during a chemical reaction.

Front

What is a product in a chemical reaction?

Back

A product is a substance that is formed as a result of a chemical reaction.

Front

What is the difference between a balanced and unbalanced chemical equation?

Back

A balanced equation has equal numbers of each type of atom on both sides, while an unbalanced equation does not.

Front

What is the significance of subscripts in a chemical formula?

Back

Subscripts indicate the number of atoms of each element in a molecule.