National Chemistry

 

1.  (a)  E  (1 mark)

     (b)  A (1 mark)

 

2.  (a)  F and A (1 mark)

     (b) B (1 mark)

 

3.  (a) E and C (1 mark)

(b) B and F (1 mark)

(c) D and E (1 mark)

 

4.   (a) D (1 mark )

 (b) C (1 mark)

 (c) E (1 mark)

 

5. (a)  A and D (1 mark)

(b)  F (1 mark )

 

6.  A and C  (1 mark each )  

(if you pick three then lose a mark for the extra answer)

 

7.    B and D (1 mark each)  

(if you pick three then lose a mark for the extra answer)

 

8. A and B (1 mark each)

(if you pick three then lose a mark for the extra answer)

 

9. A and C (1 mark each)

(if you pick three then lose a mark for the extra answer).

 

PART 2

 

10. (a) no effect

(b) cyclohexane

(c) Isomers

 

11. (a) hydrogen

(b) W is copper or silver; Y is sodium or lithium or potassium

(c) Y, X, Z, W

 

12 (a)  CH4        +      2O2 ---->   CO2 + 2H2O

(b)  if burned would release sulphur dioxide - pollutant

(c)                                    H2S       ------->  S

Write under this the number of moles

                                    2 mole of H2S  ------->  3 mole of S

Write under this the mass of these moles

                                 2 mole  x 34g ------->3 mole x 32

                                           68 g ------->     96

                                therefore   34 g ------->    48

 

(d) label both axes - copy the words from the box in the table

first box along the way "temperature / oC

second box up and down "solubility/ grams per litre";

put on the scale  along the way each large box worth 10

up the way each large box worth 25;

make sure over half the graph paper is used;

make sure it is a line graph.

plot points

join the dots

(each error loses half mark)

 

(ii) As the temperature increases the solubility of sulphur dioxide decreases.

 

13. (a) (i) ammonium phosphate

(ii) To give nutrients to plants;

to help plants grow

(b) nitric acid

(c) (i)Unaffected by heat  

 

(ii) 2 x 14    x  100  (for percentage)    =  45%

 

14.  (a)  Greater mass of ions in the Dead Sea (than in the Ocean water)

(b) any one from

sodium chloride; sodium bromide; sodium sulphate

potassium chloride; potassium bromide; potassium sulphate

magnesium etc.

Name is better as you may give the wrong formula and question does ask for name

 

(c) How many mole of calcium is 0.4 g ?

     40 g = 1 mole of Ca therefore 0.4 g is

                                                                           0.4     =   0.1 mole

                                                                           40

 

15.   (a) Right to left; B to A through the ammeter

above the ammeter is acceptable

 NOT on  the ion bridge

(b) (i) OXIDATION  (Loss of electrons)

(ii)   decreases; moves lower; drops goes to 1 (hydrogen ion  appearing makes acidic) 

 (c)   Br2 +  2e ---->; 2Br-

 

16. (a) Iron

(b) Ammonium chloride and sodium hydroxide

An ammonium compound and an alkali

 

(c) The negative electrons of one atom and positive protons of the other atom attract

one another holding the two atoms together.

 

17. (a)   Molecules which have - a general formula;

   similar chemical properties

    gradual increase in physical properties

(b) (i) hydrogen (H2)

(ii) view

 

 

18.  (a) precipitation

(b) Ca2+ (OH-)2

(c) carbon dioxide (carbon monoxide)

(d) ions can move when molten

 

19.  (a)   CnH2n-2

(b) (i) view

 

(ii) The bromines are not (on carbons) next to one another (therefore removal   will

not allow a carbon-carbon triple bond)

 

 

 

 

2001 Credit

          Hint area

          Almost the answers

           Answers.

2001 Credit                   ANSWERS