Physical Science 1st Semester Review

Front

1,221 km = ________ m

Back

1,221,000 m

Front

To convert from the base unit to milli you multiply by how many factors of ten?

Back

3

Front

Which of the following determines the identity of an element?

Back

number of protons

Front

According to the octet rule most elements need _______ valence electrons.

Back

8

Front

What is the correct Lewis Dot Structure for ammonia NH3?

Back

H | H-N-H | H

Front

What is the definition of an element?

Back

A substance that cannot be broken down into simpler substances by chemical means.

Front

What is the atomic number of an element?

Back

The number of protons in the nucleus of an atom.

Front

What is the significance of the octet rule in chemistry?

Back

It states that atoms tend to bond in such a way that they have eight electrons in their valence shell.

Front

What is the formula for calculating density?

Back

Density = Mass/Volume

Front

What is the difference between mass and weight?

Back

Mass is the amount of matter in an object, while weight is the force exerted by gravity on that mass.