You need a 75% alcohol solution. On hand, you have a 90 mL of a 70% alcohol mixture. You also have 85% alcohol mixture. How much of the 85% mixture will you need to add to obtain the desired solution

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

So the main goal for the elements is stability which is a complete/full valence shell and typically the magic number for a stable element is 8 valence electron but not always. so elements to the left of the periodic table tend to be way less stable then those on the right, so the elements on the left are much more reactive.

Hellob. will be your answer  hope this

Answerheavy water or deuterium oxide.