4.0
crude oil contains a mixture of hydrocarbons.
the table below shows the relative market demand and available supply of each
fraction.
boiling point
fraction
relative %
supply
in crude oil
relative %
demand
in °c
less than 30
2
30-160
15
liquid petroleum
gas
gasoline (petrol)
kerosene
kparaffin)
diesel
fuel and heavy
160-250
10
20
220-350
greater than
350
53
20
oils
4.1
describe how fractional distillation and cracking are used so that sufficient petrol is
produced from crude oil to meet demand.
use the information in the table, and your own knowledge.
[6 marks]

The tendency of water molecules to stick together is referred to as a) adhesion b) polarity c) cohesion d) transpiration e) evaporation

For the reaction shown, find the limiting reactant for each of the following initial amounts of reactants. 4al(s)+3o2(g)→2al2o3(s) a) 1 molal, 1 mol o2 b) 4 molal, 2.6 mol o2 c) 16 molal, 13 mol o2 d) 7.4 molal, 6.5 mol o2

Answer asap need it by wednesday morning carry out the following calculations on ph and ka of from data. i. calculate the ph of 0.02m hcl ii. calculate the ph of 0.036m naoh iii. calculate the ph of 0.36m ca(oh)2 iv. calculate the ph of 0.16m ch3cooh which has ka = 1.74 x 10-5 mol dm-3 v. calculate ka for weak acid ha which has a ph of 3.65 at 0.30m concentration vi. calculate the ka of a solution made by mixing 15.0 cm3 0.2m ha and 60.0 cm3 0.31m a-. [ph= 3.80] vii. calculate the ph of a solution made by mixing 15.0 cm3 0.1m naoh and 35.0 cm3 0.2m hcooh. [ka = 1.82 x 10-4 m]