National Chemistry

 1. (a) Tempting to use page 1 but page 4 answers it quicker.

(b)  Kr number 36; Po is 84; K is 19; P is 15; Pt is 78; Pb is 82

remember to pick 2 boxes

 

(c)  catalytic converter is used in cars  - must be solid and unreactive

Do not use leaded petrol

 

2. Identify  chemicals used to test for substances given in each question.

This should be three different answers.

Read all three questions and do in order you find easiest.

Look at the five chemicals all are used in tests try to identify what each tests for.

These last two instructions may help eliminate possible answers.

(a) Starch - a carbohydrate

(b) Glucose - another carbohydrate

(c) Unsaturated - C=C<

 

 

A. blue to orange (needs heat ) indicates what ?

B. decolourised by

C. turns blue in presence of ?

D. turns blue/black in presence of ?

E. goes milky with what ?

 

3.  (a) Look at the spelling.

remember to pick 2 boxes

(b) You have "eth", "pent", "prop" and "hex as beginnings indicating the number of carbons. Since you need TWO then both  "prop" or both "Pent" are only possibles.

(c) The more carbons the higher boiling point - check on page 6

 

4. (a) galvaniZ(n)e

(b) Page 4 of data book - look for yellow flame test

(c) Not elements ie not in Periodic table; not on paper

remember to pick 2 boxes

 

5. Six reactions you could recognise

A.     changes pH

B.     two substances add together to produce one

C.    needs electricity

D.    forms a solid

E.     burning

F.     one substance "kicks out" another

 

(a) C=C gives this away

(b) Acid reaction gives this away

 

6. Useful to know about gases.

Try and write the formula for each in the boxes to help.

A,  CH4

B.  NH3

C.  CO

D.  CO2

E.  N2

F.  O2

 

(a) pH paper blue = alkaline gas - only one known to you

(b) Carbon and hydrogen only

(c) Taken in by plant during photosynthesis

(d) Must be gases present in the air

remember to pick 2 boxes

 

7. In this style of question then there are TWO correct answers and three wrong   answers

- work through each statement individuaally deciding if it is True/ False.

Watch for statements that are the opposite of each other - both cannot be correct and one usually is.

each statement must be TRUE for both gold and silver

 

A.  page 8  numbers 47 &amp; 79  &quot;are they NOT transition metals

B.  both metals - TRUE

C.  found as pure metals ?

D.  page 7 - are these metals unreactive ? low down electrochemical series

E.  page 7 - compare to copper are they above copper in electrochemical series

 

Part 2

8. (a) Draw on diagram position of electrons found in fluorine - page 1 gives   electronic configuration of 2,7

(b) Charged particles found in atoms are positive protons and negative    electrons.

Neutral means no charge

 

9. (a) (i)  carbon dioxide is a non-metal oxide

sodium oxide is a metal oxide - group 1 metals are  the alkali metals

pH is a number

(ii) Check page 5 of the data book - the solubility tables

(b) sodium + oxygen (diatomic) ------>   sodium oxide

 

10. (a) The repeating unit is

 

3 monomer units would be 6 C joined together

(b) "thermo"  for heat - "setting" or "plastic" for softened

(c) label both axes - actually given here as "%" and "use"

put on the scale  along the way two large boxes  for each use

up the way each large box worth 5;

make sure over half the graph paper is used;

plot points

make sure it is a bar graph.

 

11. (a) definition of a catalyst is a MUST KNOW

(b) When making a statement about a relationship given in a graph you can   usually  frame your answer as follows

"As the data along the way increases then the data up the way increases or decreases (pick one)

As the temperature increases then the % SO2converted increases or  decreases (pick one)"

(c) It must be bad or dangerous!!!

(d)

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12.  (a) Breaking down a compound using ELECTRicity.

(b) The negative electrode attracts what kind of ion?

(c) Copper chloride solution - copper at negative electrode so what at positive   electrode ?

If you can SEE  - colour change; solid formed; bubbles of gas etc.

(d) Suitable for ELECTRodes.

 

13.  (a) Chemical name for rust ? = iron oxide

Gases in air ? = nitrogen and oxygen

One fifth is in bold.

(b) Larger piece of iron and same amount of air

(c) For the iron ION not compound.

Copy an iron ion from data book page 7

 

14.  (a) (i) Haber or Ostwald

(ii) nitrogen dioxide + air + X go into absorber nitric acid appears

NO2  + O2 +  X ----> HNO3

(b) Why was nitrogen chemistry so important ?

 

15. (a) (i) What is in the battery ?

What supplies the electrons ?

(ii) use your common sense.

(b) (i) Use page 7 to help electrons flow from more reactive to less reactiv

           Draw the arrow on or above the wire NOT on the potato.

(ii) Replacing a metal in a cell would increase or decrease the voltage

the bigger the gap between the metals on page 7 the higher or lower the voltage produced ?

 

16. (a) Volume at end of reaction at the longest time.

Make sure it is experiment A (it is not 22cm3 !!!)

(b) SAME volume and concentration must have something the SAME on the   graph.

(c) Must be something different between A and B at the start of the graph.

(d) Speeds up a chemical reaction but is unaffected itself.

 

17. (a) Cracking or fractional distillation ?

(b) The bigger the molecules the higher the density &amp; melting point &amp; viscosity   &amp;

ignition temperature &amp; boiling point &amp; darker the colour

(c) It is a comparison so do something to petrol and  then the same to    lubricating

oil.

The burette and beaker suggests a liquid is poured into the beaker.

 

18. (a)(i) eg  Cl2

(ii) Ionic, covalent or metallic are the types of bonding?

(b) (i)  When making a statement about a relationship given in a table you can usually frame your answer as follows "As the data in first column increases   then the data in the second column increases or decreases (pick one)"

In this case

As the Atomic number increases then the boiling point increases or decreases  (pick one)

(ii) Look at the figures and estimate the missing value make it sensible by looking at the other differences.

2001 GENERAL              ALMOST THE ANSWERS

2001 General

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              Almost the answers

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