Chemistry 9701 · AS & A Level
Hydroxy compounds
100 practice questions on Hydroxy compounds, with worked solutions and instant marking.
Which row correctly displays a primary, a secondary and a tertiary alcohol?
Feb/March 2016
An unidentified organic compound Z reacts with sodium to produce a flammable gas as one of the products. Z does not form a yellow precipitate with alkaline aqueous iodine. What could be a possible identity of Z?
Feb/March 2016
Propan-2-ol takes part in many reactions. Which row is the correct one?
Feb/March 2017
The structure of Ethane-1,2-diol is shown below. If the C-C bond is not cleaved, five oxidation products are possible. What is the combined number of aldehyde groups ($-\text{CHO}$) and carboxylic acid groups ($-\text{COOH}$) present in these five products?
Feb/March 2017
When answering this question, both structural isomerism and stereoisomerism should be taken into account. The molecular formula of compound X is $\text{C}_5\text{H}_{12}\text{O}$. Compound X: • reacts in alkaline aqueous iodine • may be dehydrated to give only two alkenes. Which compound could X be?
Feb/March 2018
How many structural isomers with molecular formula $\text{C}_4\text{H}_{10}\text{O}$ show infra-red absorptions at about $1200\ \text{cm}^{-1}$ and also at about $3400\ \text{cm}^{-1}$?
Feb/March 2018
Menthol is an alcohol that occurs naturally. If menthol is heated with concentrated sulfuric acid, a reaction takes place. Among the products produced is compound T. Which structure could compound T have?
Feb/March 2019
Only structural isomerism should be taken into account for this question. Each of the isomeric alcohols having molecular formula $\text{C}_5\text{H}_{12}\text{O}$ is added on its own to warm alkaline aqueous iodine. For how many of the isomers is a yellow precipitate produced?
Feb/March 2019
The diagram illustrates the structure of cholesterol. Which of the following statements about cholesterol are correct?
Feb/March 2019
When $\text{CH}_3\text{CH}=\text{CHCH}_2\text{OH}$ is heated under reflux with $\text{K}_2\text{Cr}_2\text{O}_7/\text{H}^+$, what skeletal formula is formed for the compound produced?
Feb/March 2020
How many tertiary alcohols are there with molecular formula $\text{C}_6\text{H}_{14}\text{O}$?
Feb/March 2021
An excess of P reacts with Q, in the presence of concentrated sulfuric acid, to produce R. Effervescence is observed when sodium is added to pure R. The structure of P is shown. Which organic compounds could compound Q be?
Feb/March 2021
The structure of tartaric acid is shown. Four moles of substance X react with one mole of tartaric acid. What might substance X be?
Feb/March 2022
The two isomeric alcohols W and X each have the molecular formula $\text{C}_4\text{H}_9\text{OH}$. When W is oxidised, it forms carbonyl compound Y, and Y produces a red precipitate with Fehling's solution. When X is oxidised, it forms carbonyl compound Z, and Z does not produce a red precipitate with Fehling's solution. Which of W and X forms a yellow precipitate with alkaline $\text{I}_2$(aq)?
Feb/March 2023
Reagent X is introduced separately to 2-methylbutan-1-ol and 3-methylbutan-2-ol. The observations seen are not the same. What is reagent X?
Feb/March 2025
Which reagent would behave differently with the two isomeric alcohols, $(\text{CH}_3)_3\text{CCH}_2\text{OH}$ and $(\text{CH}_3)_2\text{CHCH}_2\text{CH}_2\text{OH}$?
May/June 2010
Which isomer of $\text{C}_4\text{H}_{10}\text{O}$ produces three alkenes when it is dehydrated?
May/June 2010
Which reagent will react in different ways with the two isomeric alcohols, $(\text{CH}_3)_3\text{CCH}_2\text{OH}$ and $(\text{CH}_3)_2\text{CHCH}_2\text{CH}_2\text{OH}$?
May/June 2010
Which isomer of $\text{C}_4\text{H}_{10}\text{O}$ produces three alkenes when it is dehydrated?
May/June 2010
Which isomer of $\text{C}_4\text{H}_{10}\text{O}$ produces three alkenes when it is dehydrated?
May/June 2010
Using the apparatus shown below, alcohols can be converted fairly easily into alkenes such as propene in a school or college laboratory.
May/June 2010
Pentanol, $\text{C}_5\text{H}_{11}\text{OH}$, has four structural isomers that are primary alcohols. Of these primary alcohols, how many contain a chiral carbon atom?
May/June 2011
Which isomer of $\text{C}_6\text{H}_{13}\text{OH}$ produces the largest number of distinct alkenes when it is dehydrated?
May/June 2011
Compound Y is warmed with acidified potassium dichromate(VI). The organic product formed then produces an orange precipitate with $2,4$-dinitrophenylhydrazine reagent, but it does not produce a silver mirror with Tollens’ reagent. What is Y?
May/June 2011
In a primary alcohol, the functional group is $-\text{CH}_2\text{OH}$. Which reagent can react with a primary alcohol, under suitable conditions, to produce an organic product containing the same number of oxygen atoms as the alcohol?
May/June 2011
Which reagent produces the same observable result when tested with propanal and propan-2-ol?
May/June 2011
Which of the compounds, when heated under reflux with an excess of hot acidified potassium dichromate(VI), form a product containing a chiral centre?
May/June 2011
Compound Y is oxidised using warm acidified potassium dichromate(VI). The organic product formed produces an orange precipitate with 2,4-dinitrophenylhydrazine reagent, but it does not produce a silver mirror with Tollens’ reagent. What is Y?
May/June 2011
Which isomer of $\text{C}_6\text{H}_{13}\text{OH}$ produces the largest number of different alkenes when it undergoes dehydration?
May/June 2011
A primary alcohol contains the functional group $-\text{CH}_2\text{OH}$. Which reagent, when used with a primary alcohol under suitable conditions, produces an organic product containing the same number of oxygen atoms as the alcohol?
May/June 2011
Compound J is an organic compound that reacts with sodium, forming an organic ion carrying a charge of $-3$. When J reacts with $\text{NaOH(aq)}$, an organic ion with charge $-1$ is formed. What could the structural formula of J be?
May/June 2012
When compound $X$ undergoes complete combustion, the products are carbon dioxide and water only. A portion of $X$ is combined with aqueous potassium dichromate and heated under reflux for one hour. The resulting mixture is then distilled, and the only organic product obtained is collected. The collected organic product reacts with sodium to produce hydrogen, but it does not react with 2,4-dinitrophenylhydrazine reagent and it does not react with ethanol in the presence of concentrated sulfuric acid to form an ester. What conclusion can be drawn from this information?
May/June 2012
A compound $Y$ shows these characteristics. • At room temperature and atmospheric pressure, it is a liquid. • It is only partly miscible with water. • It does not produce steamy fumes with $\text{PCl}_5$. What might $Y$ be?
May/June 2012
An organic compound will turn dilute acidified aqueous potassium manganate(VII) colourless when warmed, yet it will not turn bromine water colourless. What might the organic compound be?
May/June 2012
Fumaric acid may be converted into oxaloacetic acid by a two-stage route that passes through the intermediate Q. $\text{HO}_2\text{CCH=CHCO}_2\text{H} \xrightarrow{\text{step 1}} Q \xrightarrow{\text{step 2}} \text{HO}_2\text{CCOCH}_2\text{CO}_2\text{H}$ In the laboratory, either of these stages can be carried out with a single reagent. What might the intermediate Q be, and which reagent could be used for step 2?
May/June 2012
Oxygen-containing organic compounds can have alcohol, aldehyde, carboxylic acid, ester or ketone functional groups. These functional groups can be recognised from their reactions with specific reagents. Compound X has the empirical formula $\text{CH}_2\text{O}$ and $M_r$ of $90$.
May/June 2012
Naturally occurring organic compounds often contain oxygen. They may include alcohol, aldehyde, carboxylic acid, ester or ketone functional groups. These functional groups can be recognised by how they react with particular reagents. Compound F is a white solid with molecular formula $\text{C}_3\text{H}_6\text{O}_3$. F dissolves in water. When $\text{NaHCO}_3$ is added to this solution, a colourless gas, G, is released and it turns limewater milky.
May/June 2012
Which compound produces an organic product with a lower boiling point when it is heated under reflux with an excess of acidified potassium dichromate(VI)?
May/June 2013
Crotyl alcohol, $\text{CH}_3\text{CH}=\text{CHCH}_2\text{OH}$, is a colourless liquid that serves as a solvent.
May/June 2013
Compound Q, heptan-2-one, is present in some blue cheeses. Q has the formula $\text{CH}_3(\text{CH}_2)_4\text{COCH}_3$.
May/June 2013
Compounds that contain the allyl group, $\text{CH}_2{=}\text{CHCH}_2-$, have strong, pungent odours and occur in onions and garlic. Allyl alcohol, $\text{CH}_2{=}\text{CHCH}_2\text{OH}$, is a colourless liquid that dissolves in water.
May/June 2013
X is a compound with molecular formula $\text{C}_4\text{H}_{10}\text{O}_2$. It has a straight-chain carbon skeleton and includes two OH groups. When X reacts with an excess of hot, acidified, aqueous manganate(VII) ions, it is changed into a compound with molecular formula $\text{C}_4\text{H}_6\text{O}_4$. To which two carbon atoms in the chain of X are the two OH groups attached?
May/June 2014
The compound pentan-1,4-diol contains two OH groups in each molecule and can be oxidised. Which statements concerning pentan-1,4-diol or its oxidation products are correct?
May/June 2014
Which alcohol contains a chiral centre and can be oxidised into a ketone?
May/June 2014
Among the alcohols listed, which ones cannot undergo dehydration to produce alkenes?
May/June 2014
Menthol is a naturally occurring alcohol present in peppermint oil. Which reagents react with menthol?
May/June 2014
Most alcohols may be dehydrated to form alkenes. Which alcohol may be dehydrated to form three separate isomeric alkenes?
May/June 2014
Within the Krebs cycle, one step that releases energy for the human body is the conversion of fumaric acid to malic acid. $\text{HO}_2\text{CCH=CHCO}_2\text{H} \rightarrow \text{HO}_2\text{CCH(OH)CH}_2\text{CO}_2\text{H}$ Which reagent(s) would carry out this conversion in the laboratory?
May/June 2014
Propane-1,2,3-triol is the starting material for many important industrial chemical processes. Which statements about propane-1,2,3-triol are correct?
May/June 2014
Which alcohol is oxidised by an acidified solution of potassium dichromate(VI) to form a ketone with six carbon atoms?
May/June 2015
Use of the Data Booklet is relevant for this question. $2.40\,\text{g}$ of propan-2-ol was combined with excess acidified potassium dichromate(VI). The reaction mixture was then heated under reflux for twenty minutes. The organic product was afterwards obtained by distillation. The yield of product was $75.0\%$. What mass of product was obtained?
May/June 2015
An organic compound $Z$ • is oxidised by hot acidified potassium manganate(VII), • reacts with sodium to produce hydrogen. What might compound $Z$ be?
May/June 2015
Malic acid is found in apples. Given suitable conditions, which substance reacts with just one of the $-\text{OH}$ groups in the malic acid molecule?
May/June 2015
There are four alcohols, A, B, C and D, which are structural isomers and have the molecular formula $\text{C}_4\text{H}_{10}\text{O}$. Alcohol A does not react with acidified potassium dichromate(VI) solution, whereas B, C and D do react. When all four alcohols are heated with concentrated sulfuric acid, they form products with the molecular formula $\text{C}_4\text{H}_8$. A, C and D each produce only one product in this reaction. B gives a mixture of two structural isomers, one of which displays stereoisomerism.
May/June 2015
Alcohol Y is oxidised mildly to form product Z. Z gives positive tests with Tollens’ reagent and with 2,4-dinitrophenylhydrazine reagent. What could alcohol Y be?
May/June 2016
Malic acid occurs in apples. Which reagent reacts with all three -OH groups in the malic acid molecule?
May/June 2016
Malic acid occurs in apples. Which reagent would react with only one of the $-\text{OH}$ groups in the malic acid molecule?
May/June 2016
An unidentified organic compound reacts with sodium to produce a combustible gas as one product, but it does not form a yellow precipitate with alkaline aqueous iodine. What could be a possible identity of the unknown organic compound?
May/June 2016
Q is a compound with the molecular formula $\text{C}_4\text{H}_{10}\text{O}$. Q may be oxidised using acidified potassium dichromate(VI). Q cannot be obtained by reducing a carboxylic acid with $\text{LiAlH}_4$. Identify the structure of Q.
May/June 2017
Geraniol and linalool are compounds present in certain flower fragrances. Which statement is correct?
May/June 2017
Compound X is a single, pure optical isomer. When X is heated with an excess of concentrated $\text{H}_2\text{SO}_4$, only one organic product is produced. What could X be?
May/June 2017
Which statement concerning butan-1-ol, butan-2-ol, and 2-methylbutan-2-ol is incorrect?
May/June 2017
Which compound reacts with acidified potassium dichromate(VI) and with alkaline aqueous iodine?
May/June 2017
Combustion data may be used to work out the empirical formula, molecular formula and relative molecular mass of many organic compounds.
May/June 2017
Which two alcohols are isomers of one another?
May/June 2018
Which alcohol can be dehydrated to produce two products that are structural isomers of one another?
May/June 2018
Which reagent could be used to detect alcohol in a mixture made up mainly of alkanes and alkenes?
May/June 2018
Which alcohol reacts with acidified potassium dichromate(VI) solution to form a ketone with six carbon atoms?
May/June 2018
Which compound is a secondary alcohol and, on dehydration, produces an alkene with $M_r = 70$?
May/June 2018
An ester $X$ has the structural formula $\text{CH}_3\text{CO}_2\text{CH(CH}_3)\text{CH}_2\text{CH}_3$. $X$ may be made by heating an alcohol $Y$ under reflux with ethanoic acid and an acid catalyst. What is the correct name of $Y$?
May/June 2018
$X$ has the structure $\text{CH}_3\text{CH(OH)CH}_2\text{CH}_3$.
May/June 2018
Organic compound T takes part in these reactions. • T is oxidised by hot, acidified potassium manganate(VII). • T reacts with sodium and produces hydrogen. Which compound could T be?
May/June 2019
Compound Y • reacts with alkaline aqueous iodine to produce a yellow precipitate • causes warm, acidified potassium dichromate(VI) solution to change colour. What might compound Y be?
May/June 2019
A molecule of geraniol is shown. What product is obtained when geraniol is reacted with excess cold, dilute, acidified manganate(VII) ions?
May/June 2019
Alcohol W cannot be prepared by reducing a carboxylic acid using LiAlH$_4$. When Alcohol W is dehydrated with concentrated sulfuric acid, it forms only one product. What is a possible identity for W?
May/June 2019
When answering this question, take account of structural isomerism and stereoisomerism. Which isomer of $\text{C}_6\text{H}_{13}\text{OH}$ produces the largest number of distinct alkenes on dehydration?
May/June 2019
An unidentified organic compound $Z$ reacts with sodium to produce a flammable gas as one product. $Z$ does not form a yellow precipitate with alkaline aqueous iodine. Which of the following could be the identity of $Z$?
May/June 2019
The diagram shows the structure of compound Y.
May/June 2019
One alcohol has the molecular formula $\text{C}_5\text{H}_{12}\text{O}$. It exists in several isomeric forms. Which isomer gives a yellow precipitate with alkaline aqueous iodine?
May/June 2020
What reagent could be used to tell propane-1,2-diol apart from ethane-1,2-diol?
May/June 2020
When ethene reacts with aqueous bromine, two products are formed, $\text{CH}_2\text{BrCH}_2\text{Br}$ and $\text{CH}_2\text{BrCH}_2\text{OH}$. Which statement about these products is correct?
May/June 2020
Which alcohols are not able to be dehydrated to produce alkenes? 1. $\text{CH}_3\text{OH}$ 2. $(\text{CH}_3)_3\text{COH}$ 3. $\text{CH}_3\text{CH(OH)CH}_3$
May/June 2020
Which reagent is able to react with both $-\text{OH}$ groups in lactic acid, $\text{CH}_3\text{CH(OH)CO}_2\text{H}$?
May/June 2020
Sucrose is a white crystalline solid, $\text{C}_{12}\text{H}_{22}\text{O}_{11}$. In reaction Z, sucrose is combined with water in the presence of the catalyst aqueous hydrochloric acid, forming glucose and fructose.
May/June 2020
When alcohol X is treated with concentrated sulfuric acid, a mixture of products is formed. Two of these products are structural isomers. What might X be?
May/June 2021
Cortisone is a synthetic hormone. Which class or classes of alcohol are present in this molecule?
May/June 2021
Which alcohols can be oxidised to produce an organic compound that gives coloured precipitates with both 2,4-dinitrophenylhydrazine reagent and alkaline aqueous iodine?
May/June 2021
Two reactions are depicted. $(\text{CH}_3)_2\text{CHCO}_2\text{H} \xrightarrow{\text{LiAlH}_4} \text{alcohol P}$ $\text{CH}_3\text{CO}_2\text{CH(CH}_3)_2 \xrightarrow{\text{hydrolysis}} \text{alcohol Q} + \text{acid R}$ Which classes of alcohol do P and Q belong to?
May/June 2021
Methanol, $\text{CH}_3\text{OH}$, dissolves in water since it can make hydrogen bonds with water molecules.
May/June 2021
Crotyl alcohol, $\text{CH}_3\text{CH}=\text{CHCH}_2\text{OH}$, is a colourless liquid and is used as a solvent. Under suitable conditions, crotyl alcohol reacts separately with $\text{Br}_2$, $\text{K}_2\text{Cr}_2\text{O}_7/\text{H}^+$, conc. $\text{KMnO}_4/\text{H}^+$ and $\text{PCl}_5$. Which row is the correct one?
May/June 2022
Pentaerythritol is used as an intermediate in the production of paint. Which statement is correct?
May/June 2022
But-2-ene is oxidised by $\text{KMnO}_4$ to give the organic compound $\text{Y}$. $\text{Y}$ does not react with $\text{Na}_2\text{CO}_3$. When an excess of $\text{Na}$ is added to $\text{Y}$, a gas is given off.
May/June 2022
When working through this question, take account of structural isomerism and stereoisomerism. Where a molecule has two non-identical chiral carbon atoms, there are four optical isomers. Determine the number of isomers that have: • molecular formula $\text{C}_7\text{H}_{14}\text{O}$ and • a five-membered ring and • a tertiary alcohol group?
May/June 2023
Which reagent reacts with pentan-3-ol to form a mixture of stereoisomers?
May/June 2023
Which row shows the kind of reaction that takes place when propan-1-ol reacts to form the carbon-containing product named?
May/June 2023
How many structural isomers of secondary alcohols are there for the molecular formula $\text{C}_5\text{H}_{12}\text{O}$?
May/June 2023
The general formula for a non-cyclic alcohol is $\text{C}_n\text{H}_{2n+1}\text{OH}$. For $n = 3$ and for $n = 4$, how many distinct structural isomers exist?
May/June 2023
Compound X, $\text{C}_5\text{H}_{10}\text{O}_3$, contains one chiral carbon atom in each molecule. It gives bubbles with Na but shows no reaction with $\text{Na}_2\text{CO}_3$. Which formula could be used to represent compound X?
May/June 2023
X, Y and Z are three alcohol isomers. X: $\text{CH}_3\text{CH}_2\text{CH}_2\text{CH}_2\text{CH}_2\text{OH}$ Y: $\text{CH}_3\text{CH}_2\text{CH(OH)CH}_2\text{CH}_3$ Z: $(\text{CH}_3)_2\text{C(OH)CH}_2\text{CH}_3$ Individual samples of each alcohol are heated with a mild oxidising agent and the observations are recorded. When dehydrated, one of these alcohols will form a pair of cis-trans isomers with molecular formula $\text{C}_5\text{H}_{10}$. Which row is correct?
May/June 2023
Which compound is a secondary alcohol capable of being dehydrated to produce an alkene with $M_r = 70$?
May/June 2023