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 ...

UP Board Class 12 th Chemistry paper 1 is scheduled to be held on February 20, 2018, and Paper 2 will be held on February 22, 2018. Students find chemistry a difficult subject because of the chemical ...

For example, magnesium oxide is made up of two elements, magnesium and oxygen. Its formula is MgO. This shows that it has one atom of magnesium for every one atom of oxygen.

It's important to recognise which elements are written with a subscript 2 and which are not. Take care to use the correct form in chemical equations involving these elements.

Note: This video is designed to help the teacher better understand the lesson and is NOT intended to be shown to students. It includes observations and conclusions that students are meant to make on ...