Neco Model Questions Vol1 2025 Chemistry Question 20

Practice objective / multiple choice question 20 from the 2025 Neco Model Questions Vol1 Chemistry examination.

Neco Model Questions Vol1 2025 Chemistry Objective / Multiple Choice Hard Difficulty
Question 20 NECO_MODEL_QUESTIONS_VOL1 • 2025 • CHEMISTRY • objective

Nylon‑6,6 is produced by step‑growth polymerisation of adipic acid (\(\ce{C6H10O4}\), M = 146.14 g mol⁻¹) and hexamethylenediamine (\(\ce{C6H16N2}\), M = 116.21 g mol⁻¹). In a sample the number‑average degree of polymerisation is 500. (a) Calculate the number‑average molecular weight \(M_n\) of the polymer. (b) Determine the mass percentage of nitrogen in the polymer. Give \(M_n\) in scientific notation (g mol⁻¹) and the nitrogen percentage to one decimal place.

Answer Options

A. M_n = 1.13×10^5 g mol⁻¹; nitrogen % ≈ 11.0 %
Correct Answer B. M_n = 1.13×10^5 g mol⁻¹; nitrogen % ≈ 12.4 %
C. M_n = 9.8×10^4 g mol⁻¹; nitrogen % ≈ 11.6 %
D. M_n = 1.05×10^5 g mol⁻¹; nitrogen % ≈ 13.2 %
Correct Answer
B
Correct Option:
M_n = 1.13×10^5 g mol⁻¹; nitrogen % ≈ 12.4 %

About This Question

This is Neco Model Questions Vol1 2025 Chemistry Question 20. It is one of the objective questions from the 2025 Neco Model Questions Vol1 Chemistry examination.

Difficulty level: Hard .

View More Neco Model Questions Vol1 2025 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