Chapter 2: atoms, molecules, ions

Law of conseration of mass

This law states that matter can neither be made or destroyed, the mass of the reactants is equal to the mass of the products

ex: 2H2 + o2 equals 2H2O

Law of definite proportion

A chemcial compound always have the same elecmetns in the same propotion by mass no matter the source of method of preparation 

ex: water is always in a ration of 1(hydrogen):8(Oxygen)

2 g of hydrogen combined with 16g of oxygen is 18 g of water 

Law of mutiples

When two element form more than one compound, the masses of one element that combine with a fixed mass of theother are in rations of small whole numbers

ex:carbon monooixde: 12 g of carbon + 16 g of oxygen has the same ratio as 13 g of carbon + 32 g of oxygen which is 1/2

(Question) what is the “philospohy” of chemsity

1. Each one of the elements is made up of small particles called “atoms”

2. Atoms of different elements are the same bit they differ in some way

3. Chemical compounds are made when atoms of different elements combine