Get premium membership and access questions with answers, video lessons as well as revision papers.
Mass by percentage: C=64.9%,H=13.5%. C+H+O = 100% which can be translated as 100g. Therefore, O=100% - (64.9+13.5)%
=> O = 21.6%. Therefore, C=64.9g, H = 13.5g and O = 21.6g. calculate moles of each element in the compound. This is given by: mass of element/molar mass of element from periodic table. This follows that: C = 64.9/12.0 =5.4083, H = 13.5/1 = 13.5, O = 21.6/16 = 1.35. Then divide each mole value by the smallest number of moles calculated.
=> From the calculated values, the smallest is 1.35. So...> C = 5.4083/1.35 = 4.0061 rounded off to 4, H = 13.5/1.35 = 10, O = 1.35/1.35 = 1. Thus (a) Empirical(simplest) formula of P = C4H10O. (b) Molecular formula of P is given by getting the ratio of Empirical formula mass to molecular formula mass i.e 4C+10H+1O....> 4x12+10x1+1x16 = 74. Relative formula mass = 74. 74/74 = 1. so empirical formula = molecular formula in this case, since the multiplying factor (the ratio) is 1.
raphael answered the question on May 13, 2019 at 18:27
- Gas K diffuses through a porous material at a rate of 12cm^3/s whereas S diffuses through the same material at rate of 75cm^3/s. Given that the...(Solved)
Gas K diffuses through a porous material at a rate of 12cm^3/s whereas S diffuses through the same material at rate of 75cm^3/s. Given that the molecular mass of k is 16 calculate the molar mass of s
Date posted: April 17, 2019. Answers (1)
- When excess carbon dioxide is passed over lead oxide in a combustion tube, lead (II) oxide is reduced.
(a)Write an equation for the reaction which took...(Solved)
When excess carbon dioxide is passed over lead oxide in a combustion tube, lead (II) oxide is reduced.
(a)Write an equation for the reaction which took place
(b)What observations was made in the combustion tube when the reaction was complete
(c)Name another gas which would be used to reduce lead (II) oxide
Date posted: April 16, 2019. Answers (1)
- How are sulphur(iv)oxide crystals made?(Solved)
How are sulphur(iv)oxide crystals made?
Date posted: April 15, 2019. Answers (1)
- Describe how flame tests for cations is carried out in the laboratory.(Solved)
Describe how flame tests for cations is carried out in the laboratory.
Date posted: April 12, 2019. Answers (1)
- Describe the tests for organic compounds in the laboratory.(Solved)
Describe the tests for organic compounds in the laboratory.
Date posted: April 12, 2019. Answers (1)
- Describe tests for common cations in the laboratory.(Solved)
Describe tests for common cations in the laboratory.
Date posted: April 12, 2019. Answers (1)
- Give the procedure,observation and conclusions for testing for the common anions in the laboratory.(Solved)
Give the procedure,observation and conclusions for testing for the common anions in the laboratory.
Date posted: April 12, 2019. Answers (1)
- Give the procedure,observation and conclusions for testing of common gases in the laboratory.(Solved)
Give the procedure,observation and conclusions for testing of common gases in the laboratory.
Date posted: April 12, 2019. Answers (1)
- Give detailed guidelines on how a titration should be done in the laboratory.(Solved)
Give detailed guidelines on how a titration should be done in the laboratory.
Date posted: April 12, 2019. Answers (1)
- Describe how Polymers are broken down to respective monomers.(Solved)
Describe how Polymers are broken down to respective monomers.
Date posted: April 12, 2019. Answers (1)
- Describe an experiment to show how Ethanol is broken down to Ethene.(Solved)
Describe an experiment to show how Ethanol is broken down to Ethene.
Date posted: April 12, 2019. Answers (1)
- Discuss the Fehling's test for reducing sugars.(Solved)
Discuss the Fehling's test for reducing sugars.
Date posted: April 12, 2019. Answers (1)
- Describe an experiment to show how a catalyst affects the rate of a chemical reaction.(Solved)
Describe an experiment to show how a catalyst affects the rate of a chemical reaction.
Date posted: April 12, 2019. Answers (1)
- Describe an experiment to show how temperature affects the rate of a chemical reaction.(Solved)
Describe an experiment to show how temperature affects the rate of a chemical reaction.
Date posted: April 12, 2019. Answers (1)
- Describe an experiment to show that the rate of a reaction depends on the concentration of the react(s).(Solved)
Describe an experiment to show that the rate of a reaction depends on the concentration of the react(s).
Date posted: April 12, 2019. Answers (1)
- Describe an experiment to show that the rate of a chemical reaction depends on the size of the particle of the reactant(s).(Solved)
Describe an experiment to show that the rate of a chemical reaction depends on the size of the particle of the reactant(s).
Date posted: April 12, 2019. Answers (1)
- Describe an experiment to show that there is electrical energy produced by chemical reactions.(Solved)
Describe an experiment to show that there is electrical energy produced by chemical reactions.
Date posted: April 12, 2019. Answers (1)
- Describe an experiment that can be used to determine the heat of displacement of copper.(Solved)
Describe an experiment that can be used to determine the heat of displacement of copper.
Date posted: April 12, 2019. Answers (1)
- Describe an experiment that can be used to determine the heat of neutralization of a chemical reaction.(Solved)
Describe an experiment that can be used to determine the heat of neutralization of a chemical reaction.
Date posted: April 12, 2019. Answers (1)
- Describe an experiment which shows that some chemical reactions take in heat from the surrounding.(Solved)
Describe an experiment which shows that some chemical reactions take in heat from the surrounding.
Date posted: April 12, 2019. Answers (1)