WEEK 1

Question 1

What is an Element? Define.

Answer 1

• A [pure substance] that [cannot be broken down] any further by chemical means.
• Form the [building blocks of all matter (living or non-living).

Question 2

What are the most common elements in the body?

Answer 2

• Carbon (C)
• Hydrogen (H)
• Oxygen (O)
• Nitrogen (N)

Question 3

What is an Atom? Define.

Answer 3

• The smallest unit of a chemical dement that still retains the physical and chemical properties of that element.

Question 4

What are atoms made up of? Describe in depth. Make sure to define.

Answer 4

• Made up of subatomic particles.
  -Subatomic particles: Structures that have electrical
  charge and are located in locations that are specific within the atom.
  ->Proton= +
  ->Neutron= (0)
  ->Electron= -

Question 5

What is a Nucleus? And what does it contain?

Answer 5

• The dense region found in the [centre of an atom].
  -Contains: Protons (Charge of 1+), and Neutrons (Neutral charge (0)).

Question 6

How many electrons do valence shells hold?

Answer 6

1) 2e-
2) 8e-
3) 18e-

Question 7

Atomic #= ?

Answer 7

of protons=# of electrons

Question 8

Atomic mass=

Answer 8

of protons + # of neutrons

Question 9

Elements, in general, are most stable when their outer electron shell:

Answer 9

1. is Full or…
2. Magic number of 8.
   - Elements must gain or lose electrons.

Question 10

Chlorine has an atomic number of 17. What is the chemical formula?

Answer 10

Cl-

Question 11

Potassium has an atomic number of 19. What is the chemical formula?

Answer 11

K+

Question 12

What are molecules?

Answer 12

• Combination of 2 or more atoms can [form a molecule] (e.g. O2).
• Atoms are linked through [chemical bonds].

Question 13

What are Ionic bonds? Provide definition and example.

Answer 13

• Formed when 2 atoms of opposing charges are attracted together and transfer an electron(s) to be stable.
• Compounds form neutral compounds.
  Ex) Na+ Cl- —–> NaCl.

Question 14

What are covalent bonds? Define.

Answer 14

• Share electrons with other atom(s).
• Elements (e.g. Oxygen) exert a greater “pull” on the shared electrons=highly electronegative.
  -Polar and non-polar.

Question 15

What is a Polar covalent bond? Example?

Answer 15

-Unequal sharing of electrons.
- (H20)

Question 16

What is a Non-polar covalent bond? Example?

Answer 16

-Equal sharing of electrons.
- (H2)

Question 17

What is an Inorganic molecule?

Answer 17

-Without carbon (exception CO2).
-Simple in structure.
-Made up of ionic bonds.
-Ex) Acids (HCl), Bases (NaOH), Salts (NaCl), O2, CO2, H2O.

Question 18

What is an Organic molecule?

Answer 18

-With carbon.
-Large complex molecules.
-Made up of covalent bonds.
-Allows body to carry out chemical reactions.
-Ex) Carbohydrates, lipids, proteins, and nucleic acids.

Question 19

What is water?

Answer 19

• Water consists of two hydrogen atoms covalently bonded to one oxygen atom.
  -H= partial positive.
  -O= partial negative.

Question 20

What are hydrogen bonds in water?

Answer 20

-