The mole fraction of ethylene glycol (C2H6O2) in a solution containing 20% of C2H6O2 by mass is:
1. 0.932
2. 0.0672
3. 0.832
4. 0.732
The molarity of a solution containing 5 g of NaOH in 450 mL solution is:
1. 0.188 mol dm–3
2. 0.478 mol dm–3
3. 0.378 mol dm–3
4. 0.278 mol dm–3
The molality of 2.5 g of ethanoic acid (CH3COOH) in 75 g of benzene is:
1. 0.656 mol kg–1
2. 0.616 mol kg–1
3. 0.556 mol kg–1
4. 0.456 mol kg–1
If N2 gas is bubbled through water at 293 K, how many millimoles of N2 gas would dissolve in 1 litre of water?
(Partial pressure of nitrogen = 0.987 bar, Henry’s law constant for N2 at 293 K = 76.48 kbar).
1. 0.716 mmol
2. 0.616 mmol
3. 0.726 mmol
4. 0.516 mmol