Formula and equations (1) ✅ Flashcards
a substance made up of 2 or m
what’s a compound
a substance made up of to or more different elements chemically joined together
swap….
How do we write the formulae of compounds
Swap (valencies)
Drop
Cancel
what are each of the periodic table groups valencies
group 1 valency = 1
group 2 = 2
group 3 = 3
group 4 = 4
group 5 = 3
group 6 = 2
group 7 = 1
group 8/0 = 0
what is the formulae for Hydrochloric acid
HCl
what is the formulae for nitric acid
HNo3
what is the formulae for sulfuric acid
H2SO4
what is the formulae for ethanoic acid
CH3COOH
what is the formulae for water
H20
what is the formulae for carbon dioxide
CO2
what is the term relative atomic mass used for
elements
what is the mass of carbon-12
12
what do chemists compare the masses of the atom to
to the mass of a single atom of carbon-12
what is Relative Atomic mass (Ar/RAM)
the mass number - top number
what is relative formula mass used for (Mr/RFM)
compounds
the sum of the AM of each a_ in one m_ of a c_
what is relative formula mass
the sum of the atomic mass of each atom in one molecule of a compound
what is the relative formula mass of water?
water = H20
2 x H = 2x1
1 x O = 1x16
= 2 + 16
Mr = 18
what is the Mr of potassium sulfate?
(relative formula mass)
Potassium sulfate = K2 SO4
2 x k = 2 x 39. }
1 x S = 1 x 32. } added together = 174
4 x O = 4 x 16 }
Fe2(SO4)3
what’s the mr (relative formula mass) of Iron (III) sulfate?
Iron(III)Sulfate = Fe2(SO4)3
2 x Fe = 2 x 56
3 x S = 3 x 32. }added = 400
12 x O = 12 x 16
