The processes like crystallisation, boiling, vaporisation, burning of colour, melting point, hardness etc, are called physical changes. These are reversible in nature. The processes like ...

CBSE Class 10 Science revision notes for Chapter 1 Chemical Reactions and Equations are available here. These notes are entirely according to the latest CBSE syllabus of Class 10 Science. Check these ...

It's important to remember which elements exist as molecules, and which do not. Take care to use the correct form in chemical equations involving these elements.

To balance an unbalanced equation, you need to add numbers to the left of one or more formulae. Here is one way to work out how to do this for the reaction between nitrogen and hydrogen.