Biology quiz 2

A substance which yields an anion plus a proton is a(n) ______.

Acid

(T or F) Water can dissolve only inorganic compounds.

False

(T or F) An atom that has gained or lost electrons is called an ion.

True

Atoms that form compounds are held together by chemical bonds. The bond that includes sharing electrons with another atom is called _____.

Covalent

If the outer energy level of the atom is full, it _____ react readily with other atoms.

Does not

The reactivity of an atom is due to the number and arrangement of _____ in the outer energy level.

Electrons

(T or F) A substance that releases hydrogen ions in water is a base.

False

(T or F) Of the known elements, only about 10 are needed by living things.

False

(T or F) Sodium and chlorine atoms combine because they both tend to lose electrons.

False

(T or F) The number of protons within an atom of an element is equal to its atomic mass.

False

If an atom loses or gains an electron, it is called a(n) ____.

Ion

Atoms which transfer electrons can combine to form a(n) ______ bond.

Ionic

When an atom gains an electron, it becomes ________ charged.

Negatively

A solution that contains equal numbers of hydrogen and hydroxide ions would be called _____.

Neutral

When an atom loses an electron it becomes ______ charged.

Positively

Chemical reactions are the result of an atom attempting ________________.

To rearrange its configuration to result in a stable octet.

(T or F) The symbol Na+ represents a sodium atom that has lost an electron.

True

(T or F) Water is an example of a compound.

True

If an atom has 12 electrons, how many electrons are in the n=1, n=2, and n=3 energy levels?

n=1 shell = 2 n=2 shell = 8 n=3 shell = 2