Biochem

Question 1

smallest unit of an elelment

Answer 1

atom

Question 2

every atom consists of

Answer 2

nucleus and electrons

Question 3

nucleus contains

Answer 3

protons (+) and neutrons (no charge)

Question 4

2 functions of electrons

Answer 4

1. orbit the nucleus
2. carry a negative charge to protons

Question 5

how many elements are known to make up living organisms?

Answer 5

26 elements

Question 6

6 elements occupy 97% of the mass of biological substances

Answer 6

C O H S P N (탄 산 수 황 인 질)

Question 7

when is the bond formed?

Answer 7

when atoms share electrons
- when two atoms share electrons: covalent bond
- if each atom contributes one electron, a single bond
for two electrons, double bond

Question 8

how’s the number of bonds that atom can form determined?

Answer 8

by the distribution of electons in it’s atomic orbitals - its electronic structure

Question 9

if molecules of a substance exist of atoms belonging to two elements

Answer 9

compound

Question 10

organic compounds contain this, but inorganic compounds don’t contain this. what’s this?

Answer 10

carbon

Question 11

name these three groups: NH2, CH3, COOH

Answer 11

amino group, methyl group, carboxyl group

Question 12

molecules are electrically?

Answer 12

neutral

Question 13

neutral atom lose electrons -> ?
neutral atom gain electrons -> ?

Answer 13

cation(+), anion(-)

Question 14

when a molecule or ion has an unpaired electron, it’s known as

Answer 14

radical ion

Question 15

C6H12O6 + 6O2 -> 6H20 + 6CO2 + energy
glucose + oxygen -> water + carbon dioxide + energy

Answer 15

burning involves chemical reactions converting glucose to water and CO2

Question 16

mass conservation

Answer 16

atoms are rearranged not lost or gained

Question 17

2NH2 + CO2 + H2O <-> 2NH3 + CO2