You are performing two chemistry experiments. the probability that both experiments are successful is 22%. if the first experiment is successful, the probability that the second experiment is also successful is 31%. what is the probability that the first experiment is successful?

There are numerous information's already given in the question. Based on those information's, the answer can be easily deduced. Let us now focus on the problem in hand.
Probability that both experiments become successful = 22%
Probability of the second experiment becoming successful = 31%
Probability that the
 first experiment becoming successful = 22/31
                                                             = 0.7096
Percentage that the first
experiment will become successful = 0.7096/100
                                                         = 70.97%

All the elements are arranged by melting points on the periodic table. in row they go from metals to gasses. in the row from sodium to argon, sodium is more reactive than the one on its right, magnesium.

False, as a substance changes from a solid to a liquid and from a liquid to a gas the molecules get farther apart from each other