Chemistry in Life Science

The smallest part of an element is the:

• atom

• nucleus

• molecule

Electrons have a __________ charge.

• negative

• neutral

• positive

A _______________ is a new substance formed by the chemical union of different elemtns that lose their properties and acquire new ones.

• compound

• mixture

• element

What particles are found in the nucleus of the atom?

• neutrons and electrons

• protons and neutrons

• protons and electrons

What TWO properties describe metals?

• shiny

• heat conductors

• brittle

• opaque

What's the atomic number of this element?

• 3

• 6.961

• 6

The sum of the number of protons and neutrons is called:

• atomic number

• atomic mass

• electronegativity

Ions become positive when they...

• lose electrons.

• gain electrons.

• heat up.

What kind of bonds form when a force of attraction occurs between atoms that share electrons?

• covalent

• ionic

• metallic

The balance that must exist in every organism for chemical reactions to occur is called:

• homeostasis

• photosynthesis

• electronegativity