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# tickle-my-jizzle

Questions117

• ### How do you calculate the specific enthalpy (constant volume)?

I'm trying to find the specific enthalpy of acetone (vapour, 56°C, 1 atm) from the reference state acetone (liquid, 20°C, 5 atm). There are 4 paths in the process and I've already figured out how to solve 3 of them. I'm just stuck on this one (first path):

Ac (liquid, 20°C, 5 atm) → Ac (vapour, 20°C, 1 atm)

Since there is a change in pressure and the specific volume is constant ( V = 0.0734 L/mol ), the formula I'm using is:

H = VΔP = V (1 atm - 5 atm).

I should then get an answer around 0.0297kJ/mol but I'm a little confused on the steps.

• ### How do you calculate the unit weight of air at 20°C?

I know that the general formula is p = γh and for this question, it's γ = p / (29.3)(273+20). But where does the 29.3 value come from?

PS: I'm trying to calculate the barometric pressure at an altitude of 1200m.

• ### At what elevation is the pressure of air 380 mmHg?

The temperature of the earth’s atmosphere drops about 5°C for every 1000 m of elevation above the earth’s surface. If the air temperature at ground level is 15°C and the pressure is 760 mmHg, at what elevation is the pressure 380 mmHg? Assume that the air behaves as an ideal gas.

• ### What will happen when we mix solutions A and B?

A: 100ml 0.1M CH3COOH and 0.1M CH3COONa

B: 100ml 0.1M Na2SO4 and 0.1M NaHSO4

• ### What is the pH of 1M HCl + (0.1M CH3COOH and 0.1M CH3COONa-)?

Calculate the pH after adding 1 ml of 1M HCl to a solution of 100 ml 0.1M CH3COOH and 0.1M CH3COONa-.

• ### What is the pH of 1M HCl + 0.1M CH3COOH?

Calculate the pH after adding 1 ml of 1M HCl to 100 ml of 0.1M CH3COOH. (Ksp = 1.76 * 10^-5)

• ### What is the molar solubility of MgF2 in 0.10 mol/l MgCl2?

What is the molar solubility of MgF2 (Ksp = 7.4 * 10^-11) in 0.10 mol/l MgCl2 at 25°C?

Chemistry7 years ago
• ### What is the Ksp of lithium phosphate (Li3PO4) at 18°C?

Given that the aqueous solubility is 0.034g per 100 ml at 18°C and MM=115.794 g/mol.

• ### What is the Ksp of AgOCN at 20°C?

Aqueous solubility of AgOCN (silver cyanate) is 7mg per 100ml at 20°C. The molar mass is 149.885g/mol.

• ### How do you calculate the change in entropy?

The question seems pretty simple but I can't seem to get the other values required to determine the answer.

A mass of 10kg of air at 400K is mixed with 20kg of air at 300K. Determine the change in entropy. (ANS: -0.238 kJ/K)