Unit 3 Changes in Matter Review

Front

What is an unbalanced equation?

Back

An unbalanced equation is a chemical equation where the number of atoms for each element is not equal for the reactants and products.

Front

What is a subscript in a chemical formula?

Back

A subscript is a small number written after an element’s symbol in a chemical formula that indicates the number of atoms of that specific element.

Front

Which of the following is NOT a chemical change: burning wood, rotting fruit, melting of an ice cube, rusting metal?

Back

Melting of an ice cube is NOT a chemical change; it is a physical change.

Front

What is thermal energy?

Back

Thermal energy is the total energy of all the particles in an object.

Front

What are reactants in a chemical equation?

Back

Reactants are the elements or compounds on the left side of a chemical equation.

Front

What is a balanced equation?

Back

A balanced equation is a chemical equation where the number of atoms for each element is equal for the reactants and products.

Front

What is a coefficient in a chemical formula?

Back

A coefficient is a number placed in front of a chemical formula to indicate how many molecules or moles of that substance are involved in the reaction.

Front

What is the difference between a reactant and a product?

Back

Reactants are substances that undergo a chemical change, while products are the substances formed as a result of that change.

Front

What is an example of a physical change?

Back

An example of a physical change is melting ice or boiling water.

Front

What happens during a chemical change?

Back

During a chemical change, the composition of substances changes, resulting in the formation of new substances.