Question

A cement factory emits 900 kilograms of CO2 to produce 1,000 kilograms of cement. A fully grown tree removes six kilograms of CO2 per day from the air. One acre of land can support 200 mature trees. A company builds a factory that will produce 100,000 kilograms of cement. To make the factory carbon neutral, the owners need to grow trees over an area of land measuring acres.

Answer 1

Since the factory will be producing 100,000 kilograms of cement, using the relation 1000 kg of cement = 900 kg of CO2, then the factory will be emitting 90,000 kg of CO2 at the same time. To counteract the emission, a tree can remove 6 kg of CO2 per day. Dividing 90,000 kg by 6 kg to know the number of trees, we need 15000 trees to counter the emission. Since 1 acre of land holds 200 trees, we need 75 acres of land to hold the 15000 trees.