The First Law of Thermo dynamics

Generally it is also known as Law of Conservation of Energy.
Statement:- " Energy can be neither created nor destroyed although it may be transformed from one form to another."
The law may also be stated as," The total energy of the universe, i.e. system and surroundings taken together is always constant during any physical or chemical process."
Mathematical expression ot the Law:-
dU= q + w; where dU= change in internal energy of the system;
Since w= - p dV
Hence, dU = q - p dV

Study material for a student of CBSE Class XI Science in Chemistry

What is Chemistry?

Chemisty
Chemistry is the study of atoms and molecules.
Chemistry is the study of matter, its properties and its chemical interation with other matter.
Chemistry is that branch of Pure Science that deals with matter, the constituents of matter and the chemical properties (reactions) of matter.
The Scope of Chemistry
The scope of Chemistry can be understood with the fact that everything around us, whether living or non-living is under the purview of Chemistry directly or in directly. Everything around us consists of atoms and molecules.