Calculate the vapour pressure of water at 75 °C. Take the enthalpy of vaporization of water as 40.66 kJ/mol and its boiling point as 100 °C. Calculate the change in chemical potential for a substance X with a molar mass of 100 g/mol, a density of 2 g/cm, when the pressure on it is increased by 10 bar at its melting point temperature of 25 °C.

Henry's Law constant is 0.000600 mol/kg-bar and 0.00130 mol/kg.bar for N2 and O2 respectively at 25°C. What pressure of O2 is required to achieve the same solubility as 0.616 bar of N2 in units of atm? (1 bar = 0.9869 atm; 1 atm = 760 mmHg) O 1.3 atm 0.276 atm O 4.8 x 10-7 atm O 1.3 x 106 atm O 3.5 atm

Subject: chemistry

A group of students were weighing some CaCl2(s) but they forgot to record the mass.  They know that they had 50 mL of water (you can assume water has a density of 1.00 g/mL) in the 1st test tube and the freezing point for the water by itself was measured to be -0.01 °C.  When they added the CaCl2(s) to 50 mL water in a 2nd test tube and measured the freezing point with the same thermometer they got a freezing point of -1.868°C.  The Kf value for water is 1.858 °C/m.  What was the mass of CaCl2(s) that the students added to the 2nd test tube?   Question 3 options:   3.09   1.09   1.87   2.03   2.63   1.61   0.86   2.24   2.87   2.40   1.25   1.42