Waec Model Questions Vol1 2018 Chemistry Question 6

Practice objective / multiple choice question 6 from the 2018 Waec Model Questions Vol1 Chemistry examination.

Waec Model Questions Vol1 2018 Chemistry Objective / Multiple Choice Hard Difficulty
Question 6 WAEC_MODEL_QUESTIONS_VOL1 • 2018 • CHEMISTRY • objective

A wastewater sample contains 120 mg L⁻¹ of phenol. It is treated in two successive steps: (i) aerobic biodegradation removes 40 % of the phenol present, (ii) an advanced oxidation process (Fenton's reagent) removes 75 % of the phenol remaining after step (i). The treated water is then mixed with clean water in a ratio of 1 part treated water to 3 parts clean water before discharge. What is the final phenol concentration in the discharged water (in mg L⁻¹)? Give your answer to two decimal places.

Answer Options

A. 5.40 mg/L
B. 3.75 mg/L
C. 6.00 mg/L
Correct Answer D. 4.50 mg/L
Correct Answer
D
Correct Option:
4.50 mg/L

About This Question

This is Waec Model Questions Vol1 2018 Chemistry Question 6. It is one of the objective questions from the 2018 Waec Model Questions Vol1 Chemistry examination.

Difficulty level: Hard .

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