A25.0l sample of gas at stp is heated to 55c at 605 torr. what is the new volume?

First we can find the number of moles of gas for the given volume at STP and then calculate the new volume 
Molar volume states that there 1 mol of any gas occupies a volume of 22.4 L at STP.
Therefore if 22.4 L contains - 1 mol of gas
then 25.0 L contains - 25.0 L / 22.4 L/mol = 1.12 mol 
when the pressure and temperature conditions are changed the number of moles of gas remains the same 
using the ideal gas law equation we can find the volume of the gas
PV = nRT
where P - pressure - 605 torr x 133.3 Pa/torr = 80 647 Pa
V - volume 
n - number of moles - 1.12 mol 
R - universal gas constant - 8.314 Jmol⁻¹K⁻¹
T - temperature in kelvin - 55°C + 273 = 328 K
substituting these values in the equation 
80 647 Pa x V = 1.12 mol x 8.314 Jmol⁻¹K⁻¹ x 328 K
V = 37.9 L 
new volume at the given conditions is 37.9 L

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.