1.
Which property allows iron to be picked up by a magnet?
2.
Sugar and salt cannot be told apart by testing solubility in water alone, because __________ substances dissolve in water.
3.
Sublimation is the direct change of a solid into a liquid.
4.
Why is it important to check several properties, not just one, before identifying a substance?
5.
Sugar dissolves in water, but it does not dissolve in petrol. This shows that solubility depends on the __________ used.
6.
What does this experiment show about metal and glass?
7.
According to the text, what is boiling?
8.
A metal spoon left in a glass of water dissolves, just like sugar does.
9.
In the heating experiment, candles were fixed to a metal rod and a glass rod. The candles on the __________ rod melted first.
10.
Metals conduct electricity well, but plastics do __________ conduct electricity.
11.
Solid carbon dioxide, often called 'dry ice', turns directly into a gas. This process is called __________.
12.
The temperature at which a solid changes into a liquid is called the melting __________.
13.
A diamond can scratch steel, but steel cannot scratch a diamond.
14.
For a pure substance, the melting point and the freezing point have the same temperature value.
15.
Besides iron, the metals cobalt, nickel and __________ are also magnetic.