Neco Model Questions Vol1 2020 Chemistry Question 40

Practice objective / multiple choice question 40 from the 2020 Neco Model Questions Vol1 Chemistry examination.

Neco Model Questions Vol1 2020 Chemistry Objective / Multiple Choice Hard Difficulty
Question 40 NECO_MODEL_QUESTIONS_VOL1 • 2020 • CHEMISTRY • objective

A 2.00 g sample of an unknown monoprotic carboxylic acid (M) is reacted with excess ethanol in the presence of concentrated sulphuric acid to give an ester. The isolated ester has the molecular formula \(\mathrm{C_{9}H_{18}O_{2}}\) and a mass of 2.45 g. Assuming the reaction proceeds with 1 : 1 stoichiometry between the acid and the ester, determine (a) the molar mass of the acid, (b) its empirical formula, and (c) the percentage by mass of carbon in the acid.

Answer Options

A. Molar mass = 140 g·mol⁻¹; empirical formula = C₈H₁₆O₂; %C = 68.6 %
B. Molar mass = 129 g·mol⁻¹; empirical formula = C₆H₁₀O₂; %C = 55.0 %
C. Molar mass = 115 g·mol⁻¹; empirical formula = C₆H₁₂O₂; %C = 58.0 %
Correct Answer D. Molar mass = 129 g·mol⁻¹; empirical formula = C₇H₁₄O₂; %C = 65.1 %
Correct Answer
D
Correct Option:
Molar mass = 129 g·mol⁻¹; empirical formula = C₇H₁₄O₂; %C = 65.1 %

About This Question

This is Neco Model Questions Vol1 2020 Chemistry Question 40. It is one of the objective questions from the 2020 Neco Model Questions Vol1 Chemistry examination.

Difficulty level: Hard .

View More Neco Model Questions Vol1 2020 Chemistry Questions More Neco Model Questions Vol1 Practice Questions Back to Questions

Master the Exam!

You've seen a preview, but there are thousands more questions plus AI tutor to break down complex solutions.

Unlock Full Access Available for Android & Windows
Chat with Support