Functional Groups Alcohol Aldehyde Ketone Acid Halide - UNSOLVED PRACTICE SET

Q7. Write the structural formula of any one compound containing each of the following functional groups:

(a) Aldehyde

(b) Ketone

Q8. How does a carboxylic acid differ from an alcohol in terms of:

(a) Functional group

(b) Effect on litmus paper

Q9. Name the functional groups present in:

(a) Formalin (formaldehyde solution)

(b) Rubbing alcohol (isopropyl alcohol)

Q10. Why do compounds with the same functional group show similar chemical properties? Explain with an example. 

Q11. Your mother uses vinegar (acetic acid) in cooking and baking soda (sodium hydrogen carbonate) in the kitchen. When she mixes them, bubbles form. What functional group in acetic acid is responsible for this reaction? Write the name of the gas evolved.

Q12. Distinguish between an aldehyde and a ketone on the basis of:

(a) Position of the functional group

(b) Oxidation product

Q13. Describe the following functional groups with their general formulae and one example each:

(a) Alcohol

(b) Aldehyde

(c) Ketone

(d) Carboxylic acid

Explain how the presence of a functional group determines the chemical properties of an organic compound.

Q14. Write the structural formulae of:

(a) Methanol

(b) Ethanal

(c) Propanone

(d) Ethanoic acid

For each compound, identify the functional group and state one important use in daily life.

Q15. In a school science fair, a student sets up four bottles labeled A, B, C, and D containing methanol, ethanal, propanone, and ethanoic acid respectively. The bottles have lost their labels. Design a simple experiment using litmus paper and sodium hydrogen carbonate to identify the bottle containing ethanoic acid. Explain your reasoning. 

Q16. A compound has the molecular formula C₂H₄O₂.

(a) Draw two possible structural formulae for this compound.

(b) Identify the functional group in each structure.

(c) Which of these structures would react with sodium metal to produce hydrogen gas? Explain.

Q17. A student is given four unknown organic compounds: P, Q, R, and S. The following observations are made:

Compound P turns blue litmus red.

Compound Q gives a positive silver mirror test (Tollens' test).

Compound R does not react with sodium metal.

Compound S reacts with sodium metal but does not turn litmus red.

(a) Identify the functional groups present in P, Q, R, and S.

(b) Which compound could be ethanol?

(c) Which compound could be ethanoic acid?

Q18. In your kitchen, you find the following items: lemon juice (contains citric acid), vinegar (contains acetic acid), baking soda, and antiseptic solution (contains ethanol).

(a) Identify the functional groups present in citric acid and acetic acid.

(b) Write the chemical equation for the reaction between acetic acid and baking soda.

(c) Why is ethanol used in antiseptic solutions? What property of the —OH group makes it suitable?