1. What is the name of the piece of apparatus shown?

2. Look at the graph below which shows the solubility of 3 substances in water at diferent temperatures
How many grams of solute A dissolves in 100g of water at 70°C?

3. A boy dissolved some salt in warm water. What do we call the resulting mixture?

4. Name a substance with a pH value equal to pH7

5. Pick an alkaline oxide from the list

6. About 20cm of magnesium ribbon is chopped up into 1cm lengths and placed in a crucible which is then weighed along with its lid.
The crucible is heated strongly and the lid gently raised avery few seconds.

When the reaction is over the crucible + contents + lid are all re-weighed

These are his results:

• Mass of empty crucible + lid  = 51.2g
• Mass of crucible + lid + magnesium (before heating) = 54.3g
• Mass of crucible + lid + contents (after heating) = 54.7g

 

What mass of oxygen did the magnesium react with? 

8. About 20cm of magnesium ribbon is chopped up into 1cm lengths and placed in a crucible which is then weighed along with its lid.
The crucible is heated strongly and the lid gently raised avery few seconds.

When the reaction is over the crucible + contents + lid are all re-weighed

These are his results:

• Mass of empty crucible + lid  = 51.2g
• Mass of crucible + lid + magnesium (before heating) = 54.3g
• Mass of crucible + lid + contents (after heating) = 54.7g

 

Did the magnesium gain mass, loose mass or not change in mass?
 

9. You have four substances which you label A, B, C and D.
One is a mixture, one a metallic element one a non-metallic element and one a compound.

They have the following properties:

A	A yellow, crumbly solid that burns to form a single, colourless gas which turns universal indicator red.
B	A grey, malleable solid that burns to form a single, white, alkaline oxide.
C	A colourless liquid. The liquid is warmed in a shallow dish and after a few minutes a white residue is seen.
D	A green solid that decomposes when heated to form a colourless gas and leave a black powder.

Which of the substances is likely to be a mixture ?

10. An acid would have what pH number?

11. What is the chemical formula for CHALK (calcium carbonate)?

12. Some plastic is bio readable.

What does biodegradable mean?

13. Is carbon dioxide a solid, liquid or gas?
(at normal room temperature)

14. What colour is sulphur?

15. What gas is produced when zinc is added to dilute sulphuric acid?

16. Powdered wood charcoal (carbon) is mixed with copper oxide and heated strongly.
A red glow is seen to spread though the mixture. When the mixture has cooled a pink residue is seen.

Name the two products of this reaction.

17. Name a substance with a pH value less than pH7

18. Which of the properties of metals listed below is not correct?

19. What colour will universal turn when mixed with vinegar?

20. Which of the gases below is sometimes put in balloons to make them float?