Elements, molecules and cells

Question 1

What is the smallest unit of an element?

Answer 1

Atom

Question 2

What charge do protons, neutrons and electrons have?

Answer 2

Protons - positive
Neutrons - no charge
Electrons - negative

Question 3

What are the 6 most abundant elements?

Answer 3

• Hydrogen
• Carbon
• Nitrogen
• Oxygen
• Phosphorus
• Sulfur

Question 4

What is the atomic number?

Answer 4

The number of protons

Question 5

What is the atomic mass?

Answer 5

Mass of 1 of the elements atoms

Question 6

How are bonds formed?

Answer 6

When atoms share electrons

Question 7

What is a covalent bond?

Answer 7

Where two atoms share electrons

Question 8

What is a molecule?

Answer 8

Atoms joined by covalent bonds

Question 9

What is the difference between an organic compound and an inorganic compound?

Answer 9

Organic compound contains carbon whereas inorganic doesn’t

Question 10

What is an anion?

Answer 10

A negatively charged atom (more electrons than protons)

Question 11

What is a cation?

Answer 11

A positively charged atom (more protons than electrons)

Question 12

What is a radical?

Answer 12

When a molecule or ion has an unpaired electron

Question 13

What is the principle of mass conservation?

Answer 13

Atoms are rearranged - not lost or gained

Question 14

What pH is acidic, neutral and alkali?

Answer 14

1 - acidic
7 - neutral
14 - alkali

Question 15

What are some examples of biomolecules (organic compounds)?

Answer 15

• proteins
• nucleic acids
• carbohydrates
• lipids

Question 16

What are some examples of inorganic compounds?

Answer 16

• water
• ions: (sodium (Na+), Potassium (K+), Chloride (Cl-), Calcium (Ca2+), Magnesium (Mg2+), Bicarbonate (HCO3-), Hydrogen Phosphate (HPO42-))