When non-metal atoms bond to other non-metal atoms they share electrons to form covalent bonds.   1.45 Activity. Opposites attract  Students should: 1.44 know that a covalent bond is formed between atoms by the sharing of a pair ofelectrons1.45 understand covalent bonds in terms of electrostatic attractions Play the video t...

looking for patterns

 1.38 Activity. Know your ions.  Students should: 1.38 know the charges of common ions listed You will have noted from the video that metal atoms tend to lose the electrons in their outermost electrons and form positive ions. The charge of the ion formed is equal to the number of electrons lost. Non metal atoms gain el...

the formulae of five polyatomic ions and one monatomic ion to be learnt.

 1.39 Activity. Finding formulae  Students should: 1.39 write formulae for compounds formed between the ions listed Watch the video closely pausing where instructed. Use the information given to work out the correct formulae for the following compounds: Name of compoundFormula lithium nitridepotassium oxidezinc oxidesilver chlorideLi3N&nb...

A mole of rice grains would form a huge mountain of rice with enough rice to feed the world's current population for the next 6088978 years!

 1.27 What is a mole?  Students should: 1.27 know that the mole (mol) is the unit for the amount of a substance 1.28 understand how to carry out calculations involving amount of substance, relativeatomic mass (Ar) and relative formula mass (Mr) A mole (mol) is the quantity of anything that has the same number of particles as there are ato...

Calculating the number of moles knowing the mass and the Ar ( mass of one mole) 

 1.28 Calculating moles The following masses of elements all contain one mole of atoms: 12.0 g Carbon, 32.1 g Sulphur, 14 g Nitrogen, 24.3 g Magnesium.  So if you have 24 g carbon you have 24/12 = 2 moles carbon atoms. Likewise if you have 1.4 g nitrogen you have 1.4/14 = 0.1 moles nitrogen atoms.  Rearrangin...