Remaining important questions 7.3 and all of 7.4

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• Leerjaar 3

Question 21b

1. dissolves in water
2. does not dissolve in water

Question 22

Question 24

Question 25

Question 26

Question 27

1. Sodium has to many
2. Sodium has to little
3. Sodium does not have it
4. Sodium is still developing it

Question 28a

1. molecular substance non-decomposable
2. molecular substance, decomposable
3. salt, non-decomposable
4. salt, decomposable

Question 28b

Question 28c

1. Yes, you need light
2. No, you need O2
3. Yes, you get 2 or more reaction products
4. No, you have two reactants

Question 28d

1. To prevent it from clotting
2. To keep the process visible
3. To provide light
4. To make sure algae increase in numbers

Question 28e

1. odour and colourant
2. food acid and preservative against yeast
3. food acid and colourant
4. colourant and preservative against yeast.

Question 28f

1. A
2. B
3. C
4. D

Question 28g (learn by heart!)

1. C2H6OH
2. C2H5O
3. C2H6O
4. C2H4OH

Question 28h

1. acid rain
2. smog
3. green house effect
4. flooding

Question 29a

1. adhesion
2. solubility
3. boiling point
4. particle size

Question 29b

1. solvent
2. rinsing agent
3. cleaner
4. eluent

Question 29c

1. a-c-b-d
2. b-a-d-c
3. d-b-a-c
4. c-b-d-a

Question 29d

1. filtrate
2. residu
3. emulsifier
4. catalyst

Question 29e

1. hydrophilic, tails are hydrophilic
2. hydrophilic, tails are hydrophobic
3. hydrophobic, tails are hydrophilic
4. hydrophobic, tails are hydrophobic

Na3PO4 is a

1. metal
2. salt
3. molecular substance

SiO2 is a

1. metal
2. salt
3. molecular substance

Hg is a

1. metal
2. salt
3. molecular substance

Question 33

Question 34

Question 35a

Question 35b

1. cobaltoxide
2. cobaltoxygen
3. cobalt(II)oxide
4. cobalt dioxide

Question 35c

1. 52.0/323.2 * 100% = 16.1%
2. 52.0/275.2 * 100% = 18.9%
3. 275.2/52.0 = 5.3%
4. 323.2/52.0=6.2%

Question 35d

1. filtration
2. extraction
3. evaporation
4. distillation

Question 35e

1. water
2. linseed oil
3. hexane
4. oil

Question 36a

1. smog
2. smoke
3. emulsion
4. mist

Question 36b

1. thermal decomposition
2. photolysis
3. electrolysis

Question 36c

1. A
2. B

Question 37a

1. ions (+ and -)
2. atoms
3. molecules

Question 37b

1. No NH-/OH-groups,no hydrogen bonds with water,not soluble
2. Has NH- and OH-groups,hydrogen bonds with water,soluble
3. Has OH-groups, hydrogen bonds with water,soluble
4. Has H-atoms, hydrogen bonds with water, soluble

Question 37c

1. emulsion
2. smoke
3. mist
4. foam

Question 37d

1. Air (O2, N2) has a smaller density
2. Water is not strong enough to hold the air
3. Air (O2, N2) is hydrophobic

Question 37e

1. catalyst
2. emulsifier
3. reactant
4. extra hydrogen bonds

Question 37f

1. 
2. 

Question 37g

1. ions
2. ice crystals
3. atoms
4. molecules

Question 37h

1. To mix it very well
2. To prevent demixing
3. To get the air in
4. To obtain a homogenous mixture

Question 37i

1. As a catalyst
2. As a emulsifier

0.50/1 * 100% = 50%

25/50=0.50

3.5/25 * 100% = 14%

5/25 * 100% = 20%

Question 37j

Question 37k

Question 37l

Question 37m