Physical and Ch...

Salt can be obtained by ___________ of sea water.

Iron rod turns red on heating. What kind of change is this?

Chemical formula of rust is

The diagram shows experiments involving the rusting of iron.
The following results were suggested.
1 In tube $$P$$, the iron nails rust.
2 In tube $$Q$$, the iron nails do not rust.
3 In tube $$R$$, the iron nails do not rust.
Which results are correct?

Which is an example of a chemical change?

A student is given a mixture of barium sulfate, copper(II) sulfate and water.
The table shows information about barium sulfate and copper(II) sulfate.

Which of the following is a physical change?

Two drops of dilute sulphuric acid were added to $$1g$$ of copper sulphate and then a small amount of hot water was added to dissolve it (step I). On cooling beautiful blue coloured crystals got separated (step II).Step(I) and step (II) are:

Paheli's mother made concentrated sugar syrup by dissolving sugar in hot water. On cooling, crystals of sugar got separated. This indicates:

Which of the following is a chemical change?