Help Pls pls I will give brainlist

What is the ph of a solution with a concentration of 5.2 × 10–8 m h3o+?

Why does a plastic bottle that is sealed at a high altitude change it’s shape when taken to lower altitude

Which factor is likely to impact the possible number of compounds? presence of unlimited number of elements in the periodic table the inability of atoms to align perfectly with other atoms the ability of all elements to react with every other element all elements being equally reactive