Photo AI
Most of the fuels used today are obtained from crude oil - Edexcel - GCSE Chemistry Combined Science - Question 1 - 2019 - Paper 1
Question 1
Most of the fuels used today are obtained from crude oil. (a) Which statement about crude oil is correct? A crude oil is a compound of different hydrocarbons B ... show full transcript
Worked Solution & Example Answer:Most of the fuels used today are obtained from crude oil - Edexcel - GCSE Chemistry Combined Science - Question 1 - 2019 - Paper 1
Step 1
Which statement about crude oil is correct?
Answer
The correct answer is B: crude oil is a mixture of hydrocarbons. This statement accurately reflects the nature of crude oil, which is primarily composed of various hydrocarbons that can be separated through processes like fractional distillation.
Step 2
Step 3
Choose a property. Compare how this property for kerosene compares with the property for diesel oil.
Answer
A property that can be compared is the boiling point. Kerosene has a lower boiling point than diesel oil, which is why kerosene is collected higher up in the fractionating column during fractional distillation.
Step 4
Explain, using these formulae, why butane and pentane are neighbouring members of the same homologous series.
Answer
Butane (C4H10) and pentane (C5H12) are neighbouring members of the alkane series because they differ by one -CH2- group. This difference in one carbon atom and two hydrogen atoms indicates that they are part of a continuous series where each successive compound has similar chemical properties.
Step 5
Calculate the mass of carbon in 100 g of butane.
Answer
To find the mass of carbon in 100 g of butane (C4H10):
-
Calculate the molar mass of butane:
ext{Molar mass} = (4 imes 12.0) + (10 imes 1.00) = 58.0 ext{ g/mol}
-
Find the fraction of the mass of carbon in butane:
rac{(4 imes 12.0)}{58.0} = 0.8276 ext{ (dimensionless)}
-
Multiply by the total mass:
0.8276 imes 100 g = 82.76 g
Thus, the mass of carbon in 100 g of butane is approximately 82.8 g.