Hello, can someone help me with these three homework questions? I would really appreciate it! :( 7) A sample of air at 37 oC has a volume of 486 mL. What would the volume be when the temperature is -8 oC?

8) A balloon is filled with 17.0 L of a gas at 24 oC and a pressure of 675 mmHg. What is the pressure, in mmHg, of the gas in the balloon when the temperature is 27 oC and the volume is 33.0 L?

9) A cylinder is filled with a gas at a pressure of 127.5 kPa at a temperature of 290 K. What is the temperature, in oC, when the pressure is 3.51 kPa?

the old alchemists made significant contributions to science even though there starting premises were off a bit. their conclusions after failure would steer them into better directions for investigation. science is no more than close observation and the initial mistakes result in rethinking and retrying experiments.

the best answer is d because the strong cohesion is caused by the ability of water molecules to undergo hydrogen bonding.

a is incorrect because when water solidifies, it becomes   ice, which expands and occupies a bigger volume for the same mass of water in its liquid state.

b is incorrect because water has high surface tension. besides bonding to itself it hydrogen bonds to other molecules at the top decreasing possibility for breaking of attractive forces.

c is incorrect because the water molecule has oxygen which is highly electronegative and so pulls the electron pair towards itself creating a dipole moment, making the molecule polar.

e is incorrect because water has strong adhesion, ability to stick to other molecules such as glass because of this molecules having stronger hydrogen bonding than water.