Chemistry questions to help you revise.
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No Question Answer
1 What process would you use to separate some blue dye from black ink (distillation, filtrtaion, evaporation or chromatography)?  
2 What colour does copper turn when it is heated?  
3 Flour is insoluble in water. When flour is shaken with water it will form a A: solution B: suspension C: filtrate  
4 Iron, Copper, Aluminium, Plastic. Which of these substances is used to make electric wiring.. Explain the reasons.  
5 If some salt is dissolved in warm water the water used is called the A: solution, B: solute, C: solvent ?  
6 What process of separation would you use to obtain salt from salty water (filtration, distillation or evaporation)?  
7 Iron, Copper, Aluminium, Plastic. Which of these substances is used to make the body of an aircraft.. Explain the reasons.  
8 What process of separation would you use to remove sand from salty water (filtration, distillation or evaporation)?  
9 A large lump of salt is dropped into cold water. Describe three things you could do to make the salt dissolve quicker  
10 Name a gas that relights a glowing splint  
11 Name a dense, yellow metal that is often used to make jewellery.  
12 Name any two substances found in the home that may be alkaline:   
13 Name an element that burns with a bright white flame   
14 Iron, Copper, Aluminium, Plastic. Which of these substances would you use to make a washing up bowl.. give a reason.   
15 What colour is magnesium oxide   
16 What colour is sulphur?  
17 Iron, Copper, Aluminium, Plastic. Which of these substances is usually used to make bridges. Explain the reasons.   
18 Explain some disadvantages of using iron to make bridges  
19 If some salt is dissolved in warm water the resulting mixture will be called a …… A: solution, B: solute, C: solvent ?  
20 Plastic is often used to make cheap objects like washing up bowls.. give two disadvantages of using plastic.  
21 Is sulphur a mixture, compound or element  
22 If Litmus indicator was added to a liquid of pH 5 what colour would it go?  
23 If some salt is dissolved in warm water the salt is called the A: solution, B: solute, C: solvent ?  
24 What colour would universal indicator turn when added to indigestion powder?  
25 Sugar is soluble in water. If sugar is shaken with water it will form a A: solution, B: suspension C: filtrate   
26 What chemical is formed when copper is heated in air?  
27 What process of separation would you use to obtain fresh water from salty water (filtration, distillation or evaporation)?  
28 What colour is hydrated copper sulphate  
29 Describe two things that happen when water is added to anhydrous copper sulphate  
30 Why does iron go brown when it touches copper sulphate solution?  
31 Name an element that burns to form an acidic oxide  
32 What substance is used during the test for carbon dioxide gas   
33 To show if a liquid contains water you would add it to what chemical?   
34 What colour does anhydrous cobalt chloride turn when added to water?  
35 approximately how many elements are there? a) less than 50. b) between 50 and 150 c) more than 150   
36 Pick out an alkaline oxide from the list below: A: sulphur dioxide, B: sodium chloride, C: magnesium oxide  
37 Name the liquid formed formed when blue copper sulphate decomposes:   
38 Why is lime sometimes added to garden soil?  
39 How could you show if a colourless liquid contained anything dissolved in it?  
40 Pick a neutral oxide from this list: Magnesium oxide, water, sulphur dioxide, carbon dioxide
 
41 What is the chemical test for oxygen?   
42 In a common industrial process, carbon is heated with iron oxide. What everyday substance is being produced?  
43 Iron is more reactive than copper. Describe two changes you may observe if iron is added to copper sulphate solution.   
44 Is water a mixture, compound or element?   
45 If copper sulphate were heated would it’s mass gain, get less or not change?  
46 Name a substance with a pH value less than pH7  
47 Is air a mixture, compound or element?  
48 Carbon is more reactive than copper. What two chemicals would be formed when powdered wood charcoal is heated with copper oxide?
 
49 Write the word equation for the reaction between magnesium and copper oxide
 
50 Which of these elements conducts electricity?
Sulphur, carbon, iodine, oxygen
  
51 Is carbon a metal or non-metal ?  
52 Name a chemical compound that decomposes to produce carbon dioxide when it is heated:  
53 If some copper foil were heated strongly in air would it’s mass increase, decrease or not change?  
54 If anhydrous copper sulphate is mixed with cold water , the resulting mixture is slightly warm. Why do you think this is?  
55 Name a gas that causes acid rain  
56 A piece of copper is placed into a test tube which is sealed and then weighed. The copper is heated until it goes black. The same sealed test tube + copper is now weighed again. Would the mass increase, decrease or not change?  
57 Write down the word equation for the reaction that takes place when magnesium burns  
58 Name a non-metallic element that conducts electricity   
59 Name a non-metallic element that melts easily and burns with a blue flame to form a gas with a choking smell.   
60 Name a substance that will burn completely away when heated, forming a colourless gas that turns limewater cloudy.   
61 Name a metallic element that burns in air to form an alkaline oxide   
62 Why is lime sometimes added to garden soil?   
63 A substance has a melting point of 113°C and a boiling point of 445°C. Is it a solid liquid or gas?    
64 What is the test for oxygen gas?   
65 What colour does anhydrous cobalt chloride turn when added to water?    
66 Describe two things that happen when water is added to anhydrous copper sulphate    
67 Which element has the symbol Mg?
  
68 Give the name of a natural substance made mostly of calcium carbonate.   
69 What is the normal percentage of oxygen in the air?    
70 Name the most abundant gas in the atmosphere    
71 A substance has a melting point of -39°C and a boiling point of 357°C. Is it a solid liquid or gas?    
72 What percentage of the air is nitrogen?
  
73 Name two products when magnesium reacts with zinc oxide:    
74 Name TWO substances released into the air when a candle burns.    
75 Give the name and colour of the products formed when burning magnesium reacts with carbon dioxide.    
76 Some copper foil is heated in a sealed tube until the copper stops changing colour. What gas remains in the tube?   
77 Suggest a pH value for some indigestion powder designed to cure acid indigestion.   
78 What gas is formed when sulphur burns?    
79 What gaseous product would you expect when carbon reacts with magnesium oxide?   
80 Aluminium is a common metal… what makes it so expensive to manufacture?   
81 If copper metal were heated would it’s mass gain, get less or not change?   
82 What is the chemical name for the substance we call table salt?    
83 What do we call the reaction between sodium hydroxide and hydrochloric acid.
  
84 What is the approximate percentage of oxygen in the atmosphere  
85 What would happen to a piece of copper if it were heated in a tube of nitrogen?   
86 Name one of the two products formed when sodium hydroxide reacts with hydrochloric acid hydrochloric acid.  
87 What common name is given to the chemical called sodium chloride?  
88 Name a gas that turns limewater cloudy  
89 What is the chemical test for oxygen gas ?  
90 What is the chemical symbol for oxygen?
 
91 What experiment would you do to try and convince a friend that copper sulphate is a compound?   
92 A substance has a melting point of -218°C and a boiling point of -183°C. Is it a solid liquid or gas?  
93 Aluminum is often used to make saucepans. Describe properties of aluminium that make it suitable for this.   
94 Name a gas that burns with a squeak   zy pop   

 

Chromatography
Black (copper forms copper oxide when heated)
suspension
Copper because it is a good conductor of electricity and is also ductile (can be pulled into wires)
Water is the solvent
Evaporation
Aluminium because it is light (has a low density)
Filtration
1. Grind the salt up into smaller lumps.
2. Use warm water.
3. Stir the mixture
Oxygen
Gold
Oven cleaner (caustic soda: sodium hydroxide), Indigestion powder (Milk of magnesia: magnesium hydroxide), Washing soda (sodium carbonate), Garden lime
Magnesium ribbon
Plastic because plastic is cheap, light and easily moulded
White
Yellow
Iron because it is strong and relatively cheap
Iron is heavy and can go rusty
Answer A: Solution
Plastic is not very strong and can melt easily
Sulphur is an element
Yellow. Tis is because pH 5 is a weak acid
Answer B: Solute
Blue. This is because indigestion powder contains a mild alkali
Answer A: Solution
Copper oxide. (the copper reacts with oxygen from the air)
Distillation
Blue
1. The anhydrous copper sulphate would change colour (from white to blue) and 2. It would get warm
Iron is more reactive than copper so displaces copper from the copper sulphate. The copper makes the iron look brown.]
Sulphur. Most non-metals burn to form an acid
Bubble it through limewater which will go cloudy
Add water to anhydrous copper  sulphate (or anhydrous cobalt chloride) which will change colour
from blue to pink
Answer B: There are about 100 elements.
Answer C: Magnesium oxide
Water
To neutralise the acid (lime is an alkali
Let the water evaporate. Anything dissolved would appear as a residue
Water
See if it re-lights a glowing splint
Iron
The copper sulphate solution would lose its colour and the iron would get coated with pink copper
Compound
Lose mass. This is because it gives of water vapour
Lemon juice (or any acid
Air is a mixture
Carbon dioxide and copper
magnesium and copper oxide → magnesium oxide and copper
Carbon
Non-metal
copper carbonate or calcium carbonate (there are others but I am not listing them all!
Increase because the copper combines with oxygen from the air
Because a chemical reaction takes place
Sulphur dioxide (or carbon dioxide)
The mass would not change
Magnesium + oxygen → magnesium oxide
Carbon
Sulphur
Carbon
Magnesium
To neutralize an acid soil
Solid
Re-lights a glowing splint
From blue to pink
1. Changes colour (from white to blue)
Magnesium
Chalk or limestone (or bones)
21%
Nitrogen
Liquid
79%
Magnesium oxide and zinc
Carbon dioxide and water
Magnesium oxide and carbon
Mostly nitrogen
pH 10 (anything more than pH 7 and less than pH12
Sulphur dioxide
Carbon dioxide
Aluminium uses lots of electricity to manufacture it.
Copper metal will gain mass when heated in air
Sodium chloride
Neutralization
21%
Nothing would happen
Salt (sodium chloride) or water
Table salt
Carbon dioxide
Re-lights a glowing splint
O
Heat it and show that it decomposes into two substances (water and a white powder called anhydrous copper sulphate.
Gas
Aluminium is light and doesnt burn easily
Hydrogen