Biology Section 2-1 Review: Composition of Matter

Covalent bond

Bond formed when atoms share one or more pairs of electrons

What kind of bond is formed between hydrogen and chlorine atoms?

Covalent bond

What is the difference between mass and weight?

Mass is the amount of matter in an object, and weight is how heavy something is.

The atomic number of argon is 18. Will argon tend to form bonds with other elements? Explain your answer.

No, because all of its rings will be full.

Atom

Smallest unit of an element that maintains the chemical properties of that element

Neutron

Subatomic particle has no charge and that is located in the nucleus of an atom

Compound

Substance made up of atoms of two or more different elements joined by chemical bonds

One of the kinds of particles found in the nucleus of an atom is the a. proton. b. electron. c. ion. d. boron.

a. proton

An example of a compound is a. water. b. hydrogen gas. c. oxygen gas. d. chloride ion.

a. water

The atomic number of carbon is 6. Therefore, the number of protons in a carbon atom equals a. 3. b. 6. c. 7. d. 12.

b. 6

The maximum number of electrons that can be held in the orbitals in an atom's second energy level is a. 2. b. 4. c. 6. d. 8.

d. 8

Ion

Atom, radical, or molecule that has gained or lost one or more electrons and has a negative or positive charge

Identify the elements and the number of atoms of each element in each of the following compounds: a. BO2 b. C6H12O6 c. KCl d. NH3

a. Boron-Oxygen 2 b. Carbon 6-Hydrogen 12-Oxygen 6 c. Potassium-Chloride d. Nitrogen-Hydrogen 3

Of the following elements, the one that is most likely to form ionic bonds is a. hydrogen. b. carbon. c. sodium. d. oxygen.

c. sodium