Biology Honors- Objective 1 Atoms

What are atoms?

the smallest fragment of matter

What are the components/ subatomic particles that make up an atom?

protons, neutrons, and electrons

The study of biology begins with the basic unit of matter called…

the atom

What are the similarities between covalent and ionic bonds?

1. both bonds involve an attraction between atoms

2. both give stability to elements

3. both have negatively charged electrons

The word atom comes from the Greek word..

atomos

What does the Greek word “ atomos” mean?

unable to be cut/ indivisible

What charge does a proton have?

positive ( +)

What charge does an electron have?

negative ( - )

What charge does a neutron have?

neutral

What is a chemical element?

a pure substance that consists entirely of one type of atom

The number of protons in an atom of an element is called

the atomic number

example - Carbon has 6 protons, so its atomic number is 6

What is the sum of the protons and neutrons in the nucleus of an atom called?

the mass number

What are isotopes?

atoms with the same number of protons but different numbers of neutrons

True or false - Each isotopes has a different number of neutrons.

True

List 3 facts about isotopes

• all isotopes of an element have the same chemical properties

• some are radioactive

• each isotope has a different number of neutrons.

Can radioactive isotopes be used?

Yes

What are radioactive isotopes used for?

1. to determine the ages of rocks and fossils

2. to treat cancer

3. to kill bacteria that causes food to spoil