Chemistry Semester 1 Exam Study Guide

Front

What describes a solid?

Back

Its particles are packed together tightly.

Front

What is a hypothesis?

Back

A proposed explanation for what is observed.

Front

In the reaction iron + oxygen → iron oxide, what is iron?

Back

Iron is a reactant.

Front

What distinguishes a physical change from a chemical change?

Back

A different chemical composition.

Front

Identify the false statement about Mars rocks.

Back

Analysis of sunlight indicates the presence of oxygen on the sun’s surface.

Front

What is the definition of a chemical reaction?

Back

A process that leads to the transformation of one set of chemical substances to another.

Front

What is mass conservation in a chemical reaction?

Back

Mass is neither created nor destroyed in a chemical reaction.

Front

What is the difference between an element and a compound?

Back

An element is a pure substance that cannot be broken down, while a compound is made of two or more elements chemically combined.

Front

What is the law of definite proportions?

Back

A chemical compound always contains its component elements in fixed ratio by mass.

Front

What is an example of a physical change?

Back

Melting ice is a physical change.