3.1: Chemical measurements

Question 1

What is the law on the conservation of mass?

Answer 1

Law​ ​of​ ​conservation​ ​of​ ​mass:​ ​no​ ​atoms​ ​are​ ​lost​ ​or​ ​made​ ​during​ ​a​ ​chemical reaction​ ​so​ ​the​ ​mass​ ​of​ ​the​ ​products​ ​=​ ​mass​ ​of​ ​the​ ​reactants

Question 2

What is relative formula mass?

Answer 2

It is the sum​ ​of​ ​the​ ​relative​ ​atomic​ ​masses​ ​of
the​ ​atoms​ ​in​ ​the​ ​numbers​ ​shown​ ​in​ ​the​ ​formula.
o e.g.​ ​for​ ​HCl:​ ​Mr=​ ​1​ ​+​ ​35.5​ ​=​ ​36.5