The table shows the properties of some common rocks.
Which rock would be the best to use to make roof tiles?
|Soft, permeable, and easy to crumble||Waterproof (impermeable) and can be split into thin pieces||Heavy, shiny, and waterproof|
Rocks can be classified according to a hardness scale. The hardest rocks cannot be scratched. Softer rocks can be scratched with a fingernail or a coin.
A class tested four rocks by scratching them with their fingernails, a coin, a knife, and a shard of glass. They recorded their results in the table shown.
Order the rocks from hardest to softest using the results given.
We can test how permeable a rock is by placing it in water. If the rock soaks up water, it releases air bubbles.
Which two rocks shown are permeable?