15 cm3 of a gaseous hydrocarbon requires 90 cm3 of oxygen for complete combustion, both volumes being measured at 15C and 1 atm. The formula of the hydrocarbon is A C4H6
B C4H8
C C4H10
D impossible to calculate without knowing the molar volume of gases under these conditions.

1. combine iron and copper (ii) sulfate solution. (hint: iron will form the iron (iii) ion) fe + cuso4 → 2. combine lead (ii) nitrate and potassium iodide solutions. pb(no3)2+ kl → 3. combine magnesium metal and hydrochloric acid solution. mg + hcl → 4. electrolysis (splitting) of water. h2o → 5. burning magnesium. mg + o2 →

The clouds are grey and ground is wet. a quantitative b qualitative

Most materials are not magnetic because their magnetism has worn off. their magnetic domains are arranged randomly. they lack magnetic fields. earth’s heat has destroyed their magnetism.