Elements, Compounds and Mixtures — Science STD 7 — Question

If a few drops of milk are added in the experiment given the reddish colour seen from the front becomes an intense red. However, if many more drops are added the reddish colour is not seen. Why is this so?

Name the method you will use to separate the following mixtures:

1. Cream from buttermilk.
2. Mud from muddy water.
3. Stones from grains.
4. Tea leaves from boiled tea.
5. Salt from water.
6. Kerosene and water.
7. Blood cells and plasma.
8. Ink from water

What will happen if the root-tip is injured?

What would be the difference perceived between hearing only two pupils in the class talking to each other and all the children talking to one another at the same time?

Who discovered the process of fermentation?

Why are leather articles like purses, wallets, belts, footwear always polished before storing away?

What are called prop roots?

What is atmospheric pressure?

A cart with mass 20 kg went 50 m in a straight line on a plain and smooth road when a force of 2 N was applied to it. How much work was done by the force?

How will you check with the help of soap powder whether water is hard?