If one-fourth of the radioactive sample is remaining then how many half-lives have passed? 1
2
3
4
5

Why doesn't heat added to water make the tempature rise above 100c

Why is permeable soil best for plants that need a lot of drainage?

Nitrogen dioxide decomposes according to the reaction 2 no2(g) ⇌ 2 no(g) + o2(g) where kp = 4.48 × 10−13 at a certain temperature. if 0.70 atm of no2 is added to a container and allowed to come to equilibrium, what are the equilibrium partial pressures of no(g) and o2(g)