If the boiling point of a certain amount of a liquid is 150 degrees, what is the boiling point of twice that amount of the liquid?

Boiling point stays the same, because it is not dependent on volume of the liquid. Boiling point is defined as temperature at which the liquid changes into vapour. It may depend on pressure, but it never depends on volume!

Mass is the amount of matter in an object.  weight is the measurement of the pull of gravity on an object.  say for example, you travel to the moon which has a different gravitational field compared to the gravitational field of earth. (gravitational fields: earth = 1, moon = 0.165)  now when you are on the moon, the pull of gravity on you is different than on the earth. and as weight is the measurement of the pull of gravity on an object, that means yes, your weight can and will change on the moon.  however, on the moon, on earth or even on jupiter, the amount of mass inside of you remains the same. meaning your physical mass remains constant.  in conclusion it is possible for your weight to change as your mass remains constant.