Question

Poisonous gas, which was heavier than air, was used in World War I. Why might gas be a more effective weapon against soldiers in the trenches than those on the battlefield?

Answer 1

Answer:

Mustard gas is not an effective killing agent (though in high enough doses it is fatal) but can be used to harass and disable the enemy and pollute the battlefield. Delivered in artillery shells, mustard gas was heavier than air, and it settled to the ground as an oily liquid