Question

A chemical process dissolves 500 milligrams of iron oxide every 20 minutes. How long would it take this reaction to dissolve 2 lbs of iron oxide?

Answer 1

Answer:

36290 min = 604.8 hr.

Explanation:

• Knowing that:

1 lbs = 453.59237 grams.

∴ 2 lbs = 907.18474 grams.

Using cross multiplication:

500 mg of iron oxide dissolved → 20 minutes.

907184.74 mg of iron oxide dissolved → ??? minutes.

∴ The time needed to dissolve 2 lbs of iron oxide = (907184.74 mg)(20 min)/(500 mg) = 36290 min = 604.8 hr.