Chemical formula

Question 1

K(w)

Answer 1

ionic production of water; K(w) = [H+][OH-] = (10^-7)(10^-7)= 10^-14

Question 2

Dilution entail
Dilution factor
of 1 in 10

Answer 2

Entail: 1 volume of material & 9 volume of diluent
Factor: 1 + 9 = 10

Question 3

10ml glucose in 90ml water = ___fold dilution

1L glucose in 1L water = __ fold dilution

Answer 3

• 10 fold

- 2 fold

Question 4

1 pH unit = ?

Answer 4

10 fold difference in[H+] concentration

Question 5

Dilution expression

Answer 5

20ml acid & 80 ml water
2 in 10
2:8

Question 6

Number of Moles formula

Answer 6

no of moles = actual mass (g) / molar mass (gmol^-1)

Question 7

Amu of C used as standard because?

Answer 7

Mass of Carbon atom is the exact 12g as its atomic mass. It’s used as the standard

Question 8

Avogardro ‘s number

Answer 8

6.02 x 10^23

Question 9

• Mass of H2CO3 with 0.1M in 1L
• Mass of H2CO3 with 0.2M in 500ml
• Mass of H2CO3 with 0.02M in 5L
• Molar mass of H2CO3

Answer 9

• Mass of H2CO3 with 0.1M in 1L > 0.1 - mole in 1L > 2+12+48= 62 amu > 0.1 X 62 amu x (6.02 x 10^23) = 6.2g
• Mass of H2CO3 with 0.2M in 500ml > 0.2 mole in 1L > 0.1 mole in 500ml> 0.1 x 62 amu x (6.02x 10^23) = 6.2g
• Mass of H2CO3 with 0.02M in 5L > 0.02mole in 1L > 0.1 mole in 5L > 0.1 X 62 amu x (6.02 x 10^23) = 6.2g
• molar mass of H2CO3 2+12+48= 62 gmol^-1

Question 10

1M = how many mole in 2L

10M = how many mole in 1L

10M = how many mole in 500ml

10M = how many in 5L

10 mole/dm^3 = how many mole in 1L

10 mole/dm^3 = how many mole in 5L

10 mole/dm^3 = how many mole in 500ml

Answer 10

1M = how many mole in 2L 2 moles

10M = how many mole in 1L 10 moles

10M = how many mole in 500ml 5 moles

10M = how many in 5L 50 moles

10 mole/dm^3 = how many mole in 1L 10 moles

10 mole/dm^3 = how many mole in 5L 50 moles

10 mole/dm^3 = how many mole in 500ml 5 moles

Question 11

Formula for concentration

Answer 11

Concentration= no of mole/ volume

Question 12

Molar = concentration = molarity T/F

Answer 12

True

Question 13

Milli mole =
Micro mole =
Nano mole =

Answer 13

Milli mole = 10^-3
Micro mole = 10^-6
Nano mole = 10 ^-9

Question 14

Unit for molar mass

Answer 14

gmol^-1

Question 15

Formula for mass of atom

Answer 15

= amu x ( 6.02 x 10^23)

Question 16

Unit for concentration
Unit for molar =
Unit for atomic mass =
Unit for mass of atom/molecule =

Answer 16

Unit for concentration = molarity = mole/dm^3
Unit for molar = M
Unit for atomic mass = amu
Unit for mass of atom/molecule = g

Question 17

Formula for dilution

Answer 17

C1V1 = C2V2

Question 18

Conjugated pair

Answer 18

Conjugated pair: 1 e- difference to its weak acid/ base pair

Question 19

Hydrophillic-

Hydrophobic -

Answer 19

Hydrophillic- polar, dissolve in water

Hydrophobic - non-polar, fear water

Question 20

Ionic compound

Answer 20

a compound with a positive or negative

Question 21

Weak electrolytes

Answer 21

ionise only partially (weak acids & bases, eg. acetic acid, carbonic acid, phosphoric acid, NH3)

Question 22

Strong electrolytes

Answer 22

ionise completely (strong acids & bases eg. HCl, KOH)

Question 23

Electrolytes

Answer 23

molecules which dissociate (dissolve in water, ionise) to form charged ions, positive or negative.

Question 24

What is strong acid/ strong base

Answer 24

H+ donor / H+ acceptor; Completely dissociated

Question 25

What is weak acid/ weak base

Answer 25

H+ donor / H+ acceptor– Partially dissociated

Question 26

What is acid

Answer 26

proton donor

Question 27

What is base

Answer 27

proton acceptor

Question 28

Buffer solution

Answer 28

a weak acid & its conjugated pair, used to resist the pH change

Question 29

pH formula

Answer 29

pH = -log10 [H+]

pOH = -log 10 [OH-] > pH14 – pOH = pH

Question 30

What is pH

Answer 30

a measure of concentration of H+