Separation of Substances — Science STD 6 — Question

Why can our elbow not move backwards?

What kind of impurity present in water can be separated by sedimentation?

From where does a lake get water?

Are all the physical changes reversible?

Lemonade is prepared by mixing lemon juice and sugar in water. You wish to add ice to cool it. Should you add ice to the lemonade before or after dissolving sugar? In which case would it be possible to dissolve more sugar?

What happens when North pole of a magnet is brought in contact with the South pole of the other magnet?

From where do the wells or tubewells get water?

Name two gases which are soluble in water.

Where does the water flowing through the rivers and streams finally get collected?

Which method of cooking is used for preparing rice?