What is a chemical element?

How many valence electrons does an atom with five total electrons have?

a) 5.

b) 7.

c) 3.

d) 2.

e) 1.

Which of the following is true about electron energy shells?

a) They represent regions around the nucleus in which the electrons orbit.

b) The shells closest to the nucleus contain electrons with higher energy.

c) They contain electrons of the same energy.

d) a and b only.

e) a and c only.

A neon atom (Ne) is unreactive for which of the following reasons?

a) It has 7 valence electrons.

b) It has 8 valence electrons.

c) Its valence shell is full of electrons. 

d) It has 20 valence electrons.

e) b and c only.

How many electrons does an Oxygen atom need to fulfill the octet rule by filling its valence shell?

a) 8.

b) 4.

c) 1.

d) 2.

e) 6.

DRAW IT Diagram the electronic configuration of a carbon atom.

The term trace elements refers to

a. the elements CHONPS.

b. vitamins.

c. nitrogen, phosphorus, and sulfur.

d. small mineral requirements.

e. toxic substances.

Using the periodic table, answer the following questions:

a. What is the atomic number for lithium (Li)?

b. What is the atomic mass of oxygen (O)?

c. What is the chemical symbol for potassium?

d. How many protons does nitrogen have?

e. How many neutrons does lead have?

What ions result when hydrogen donates one electron to fluorine?