Biology 1010 - Chapter 2 - Essential Chemistry for Biology

Palmitic acid is a saturated acid. What does it mean to be a saturated acid?

a. It has as much water as it can hold.
b. It has as many protons as possible.
c. It has as many hydrogen atoms as possible.
d. All of these are correct.

What determines whether an atom is chemically reactive?

a. The number of protons in the nucleus.
b. The number of electrons in the electron shell.
c. The number of electrons in the nucleus
d. The number of neutrons in the nucleus

What causes the formation of ions?

a. Gain or loss of neutrons
b. Gain or loss of electrons
c. Gain or loss of protons
d. Sharing of protons

What determines the atomic number of an atom?

a. The number of protons it possesses
b. The number of electrons and protons
c. The number of neutrons it possesses
d. The number of electron shells the atom possesses.

Which of the following has a covalent bond?
(The atomic number for Na = 19, Cl = 17, H = 1, O = 16, K = 19)

a. NaCl (table salt)
b. KC1 (potassium chloride)
c. H2O (water)

Which of the following is a definition of a hydrogen bond?

a. weak chemical bond formed by two molecules each containing polar covalent bonds themselves

b. An attraction between two ions

c. The sharing of electrons between two atoms

d. An atom with more protons than electrons

Assuming the atom does not have a charge, how many electrons does a lithium (atomic number = 3, atomic weight = 7) atom have?

a. 2
b. 3
c. 4
d. 5

Assuming the atom does not have a charge, how many protons does a chlorine (atomic number = 17, atomic weight = 35) atom have?

a. 16
b. 17
c. 18
d. 19

Why is water called the solvent of life?

a. it reduces temperature of the environment.

b. It is denser than ice.

c. It dissolves a large number of molecules.

d. It has surface tension that makes it possible for plants to transport water.

An atom can be changed into an ion by adding or removing _______.
An atom can be changed into a different isotope by adding or removing _______.

If you change the number of _______, the atom becomes a different element.

A nitrogen atom has 7 protons, and the most common isotope of nitrogen has 7 neutrons. A radioactive isotope of nitrogen has 9 neutrons.

What are the atomic numbers and mass numbers of the stable and radioactive forms of nitrogen?

Why are radioactive isotopes useful as tracers in research on the chemistry of life?

Some people in your study group say they don't understand what a polar molecule is. You explain that a polar molecule...

a. is slightly negative at one end and slightly positive at the other end.

b. has an extra electron, giving it a positive charge.

c. has an extra electron, giving it a negative charge.

d. has covalent bonds.

Most basic unit of any element?

Carbon, lead, gold...?

_______ ________ are the fundamental building blocks of an atom.

Define the element?

Number of protons equal to _______ ________.

_______ and _______ make up nucleus of an atom.

Number of _______ in an element cannot change. Number of _______ and _______ can.

Negative (-) charge?

No electric charge?

Neutrons are slightly bigger than _______.

Tells how many protons and electrons.

Tells how many protons and neutrons.

Attractions between atoms or molecules?

Unequal share of electrons?

Equal share of electrons?

An attraction between atoms that share one or more pairs of electrons?

An attraction between two oppositely charged ions?

Tendency of atoms to prefer having eight electrons in valence shell.

_______ is the measure of how much you want electrons (e-.)

Water is _____.

In a water molecule _______ bonds exists between the oxygen and hydrogen atoms.

In a water molecule, oxygen pulls electrons closer together which results in a partial _______ charge.

_______ has the ability to dissolve material.

_______ has a high heat capacity.

Water is where _____ takes place.

A person who's cells cannot break down and absorb lactose is _______ _______.

An _______ is a substance that cannot be broken down into other substances by chemical reactions.

Number of naturally occurring elements?
(ex. carbon, oxygen, gold)

_______ of the 92 natural occurring elements are essential to humans.

Anything that occupies space and has mass?

Found on Earth in three physical states.

All _______ is composed of chemical elements.

A measure of the amount of material in an object.

_______ _______ are required in only very small amounts, but humans cannot live without them.

Substances that contain two or more elements in a fixed ratio.

The smallest unit of matter that still retains the properties of an element.

Each element is made up of one kind of _______.

Neutrons determine _______.

_______ are composed of subatomic particles - protons, electrons and neutrons.

Single unit of positive (+) electrical charge.

Electrically neutral (no charge) subatomic particle.

Single unit of negative (-) electrical charge.

Atoms central core

_______ rotate around nucleus in a spherical cloud of _______ charge.

Atom is _______when number of protons and electrons are equal.

Number of protons and electrons.

Atomic number 6 = ___ protons and ___ electrons.

Sum of protons + neutrons.

_______ = 1/2000 the mass of a proton.

Expressed in unit called daltons.

Close to mass number.

_______ _______ represents average of all naturally occurring forms of element.

Carbon - 12, Carbon - 13, Carbon - 14

_______ differ in mass.

Same number of protons and electrons as a standard atom.

Nucleus decays spontaneously, shedding particles and energy.

Radiation from decaying _______ can damage cellular molecules and pose serious health risks.

_______ _______ can cause harm when uncontrolled, but have many uses in biological medicine.