Simple Chemistry in Biology

Question 1

Element:

Answer 1

In chemistry, refers to a simple substance that cannot be broken down into smaller parts or changed into another substance. The basic part of an element is an atom, which contains protons, neutrons, and electrons. All atoms of an element have the same number of protons.

Question 2

Compound:

Answer 2

a substance made from two or more different elements that have been chemically joined. Examples of compounds include water (H2O), which is made from the elements hydrogen and oxygen, and table salt (NaCl), which is made from the elements sodium and chloride.

Question 3

Symbol for Carbon:

Answer 3

C

Question 4

Symbol for Hydrogen:

Answer 4

H

Question 5

Symbol for Oxygen:

Answer 5

O

Question 6

Symbol for Nitrogen:

Answer 6

N

Question 7

Symbol for Phosphorus:

Answer 7

P

Question 8

Symbol for Sulfur:

Answer 8

S

Question 9

Subatomic Particles:

Answer 9

A Subatomic particle is nothing but a particle which is smaller than an atom in size. Typically, an atom can be broken down into three subatomic particles, namely: protons, electrons, and neutrons.

Question 10

Cloud of Negative Charge:

Answer 10

The electrons are located in the electron cloud and have a negative charge. The protons have a positive charge and are located in the nucleus. Just like protons, neutrons are also located in the nucleus.

Question 11

Nucleus:

Answer 11

In 1911, Ernest Rutherford discovered that at the core of every atom is a nucleus. Atomic nuclei consist of electrically positive protons and electrically neutral neutrons. These are held together by the strongest known fundamental force, called the strong force.

Question 12

Protons:

Answer 12

A proton is a subatomic particle found in the nucleus of every atom. The particle has a positive electrical charge, equal and opposite to that of the electron.

Question 13

Neutrons:

Answer 13

A neutron is a subatomic particle found in the nucleus of every atom except that of simple hydrogen. The particle derives its name from the fact that it has no electrical charge; it is neutral. Neutrons are extremely dense.

Question 14

Electrons:

Answer 14

An electron is a negatively charged subatomic particle that can be either bound to an atom or free (not bound).

Question 15

Atomic Mass:

Answer 15

Concentrated in the nucleus, comprised of protons and neutrons in an atom.

Question 16

Atomic Number:

Answer 16

Number of protons, unique to that element

Question 17

Isotope:

Answer 17

Two or more types of atoms that have same atomic number, (protons in nuclei), but have different mass numbers due to different numbers of neutrons in their nuclei

Question 18

Radioactive Isotope:

Answer 18

Nucleus decays spontaneously, giving off particles and energy

Question 19

What determines interactions between atoms?

Answer 19

Number of valence electrons (for an atom to be stable, it must have a full outer shell)

Question 20

Chemical Bond:

Answer 20

An attraction between two atoms, resulting from a sharing of outer-shell electrons

Question 21

Covalent Bond:

Answer 21

The sharing of a pair of valence electrons by two atoms. Example: Nonmetals and nonmetals

Question 22

Single Bond:

Answer 22

Pair of shared electrons

Question 23

Double Bond:

Answer 23

Sharing two pairs of electrons

Question 24

Electronegativity:

Answer 24

Ability of an atom of an element to attract electrons when the atom is in a compound

Question 25

Nonpolar Covalent Bond:

Answer 25

Electrons are shared equally between two atoms of similar electronegativity.

Question 26

Polar Covalent Bond:

Answer 26

One atom is bonded to more electronegative atom, sharing electrons unequally

Question 27

Definition of Polar:

Answer 27

A structure having an uneven distribution of electron density.

Question 28

Dynamic Chemical Equilibrium:

Answer 28

Point at which concentrations are stabilized at a particular ratio, reactants are converted to products and vice versa. This is an ongoing process.