CHEMY 101
Test 2
Shukri
33093777
1ST Semester 2023 / 2024
Hasan Shukri 33093777
Chemy 101
Q1. Consider the following reaction:
H2S + Cl2 → S + 2HCl
Oxidized Reduced
a Cl2 S
b H2S Cl2
c Cl2 H2S
d S HCl
e HCl H2S
Q2. What is the mass of KI (MM = 166 g/mol) required to prepare 250 mL of 1.80 M
solution?
(a) 98.2g (b) 74.7g (c) 1.48g (d) 116g (e) 237g
Q3.How much water should be added to 505mL of 0.315 M HCl to dilute it to 0.200
M?
(a) 631ml (b) 126ml (c) 757ml (d) 404ml (e) 290ml
Q4.What volume of 35.0% NaNO3 (MM is 85.01 g/mol) aqueous solution contains
0.55 mol of NaNO3 ? Density of solution is 1.28 g/ml .
(a) 104.4 ml (b) 66.4 ml (c) 93.0 ml (d) 58.1 ml (e) 85.4 ml
Q5. 45.5g of KNO3 (MM = 101.1 g/mol) was dissolved in 345 ml of aqueous solution
(density of solution = 1.25 g/ml). What is the molality of the solution?
(a) 1.92 m (b) 1.17 m (c) 1.64 m (d) 0.887 m (e) 0.443 m
Q6. If the mole fraction of NaOH in an aqueous solution is 0.250, calculate its
molarity if the density of the solution 1.20 g/mL
(a) 8.44 M (b) 4.30 M (c) 2.82 M (d) 6.96M (e) 12.76 M
Q7.What is the percentage by mass of 2.75m (molal) aqueous solution of Na2CO3
(MM = 106.0 g/mol) ?
(a) 18.9% (b) 15.7% (c) 10.8% (d) 22.6% (e) 30.3%
1ST Semester 2023 / 2024
Hasan Shukri 33093777
Chemy 101
Q8.What is the vapour pressure at 85°C of a solution prepared from 100mL of water
(density 1.00 g/mL) and 90.0g of diglyme, C6H14O3, (MM is 134.2 g/mol), a
nonvolatile substance? The vapour pressure of pure water at 85°C is 534 mmHg
(a) 533 mmHg (b) 471 mmHg (c) 476mmHg (d) 517 mmHg (e) 617 mmHg
Q9. What is the freezing point of an aqueous solution of KCl whose boiling point is
101.1 °C? ( Kf = 1.86 °C/m , Kb = 0.52 °C/m)
(a) -0.52 °C (b) -2.9 °C (c) -4.3 °C (d) -6.8°C (e)-3.9°C
Q10. 65.21 g of a non electrolyte compound was dissolved in 286ml aqueous solution.
The osmotic pressure of the solution is 23.2 atm at 50 °C. Find the molar mass of the
compound.
(a) 450g/mol (b) 285g/mol (c) 261g/mol (d) 180g/mol (e) 225 g/mol
Q11. In the following figure, there are two aqueous solutions (A & B) separated by a
semipermeable membrane. Based on the osmosis principle, which of the following
statement is correct?
(a) Glycerol molecules move from the solution A to the solution B
(b) Sucrose molecules move from the solution A to the solution B
(c) Water molecules move from the solution B to the solution A
(d) Water molecules move from the solution A to the solution B
(e) Both (b) and (d) are correct
1ST Semester 2023 / 2024
Hasan Shukri 33093777
Chemy 101
Q12. A balloon filled with helium has a volume of 1.28 x 103 L at sea level where the
pressure is 0.998 atm and the temperature is 31 °C the balloon is taken to the top of a
mountain where the pressure is 0.753 atm and the temperature is -25 °C what is the
volume of the balloon at the top of the mountain?
a) 4.11 x 103 L b) 3.50 x 103 L c) 1.52 x 103 L d) 1.38 x 103 L e) 2.77 x 103 L
Q13. what is the osmotic pressure of 0.125 M solution of K2SO4 (aq) at 25.0 °C
a) 6.12 atm b) 12.2 atm c) 5.91 atm d) 9.18atm e) 8.44 atm
Q14. A solution is prepared by mixing 25.0 g of naphthalene (C10H8) with 0.750 L of
liquid CS2 (density= 1.263 g/mL). What is the concentration of naphthalene in parts per
million (ppm)?
a) 7.34 x 104 ppm b) 5.01 x 104 ppm c) 2.57 x 104 ppm
d) 2.96 x 104 ppm e) 4.62 x 104 ppm
Q15. A 10.00 g of an organic compound is dissolved in 50.00 g of benzene (kf= 6.940
°C/m). The freezing point of the solution is 1.280 °C below that of pure benzene. What is
the molar mass of the compound?
a) 1084 g/mol b) 2169 g/mol c) 1627 g/mol d) 3253 g/mol e) 776.5 g/mol
Q16. A Sample of oxygen gas (O2) is collected over water at 25.0"C. The wet gas
occupies a volume of 7.28 L at a total Pressure of 1.25 atm. How many moles of oxygen
are collected? The vapour Pressure of water is 23.8 rnmHg at 25.0°C.
a) 0.362 mol b) 0.462 mol c) 0.213 mol d) 0.725 mol e) 0.181 mol
Q17. How many grams of nitrogen gas must be added to a 6.0 L cylinder containing 6.65
gram of oxygen gas at 20°C to get a total pressure of 4.5 atm?
a) 25.6g b) 11.2g c) 6.4g d) 22.5g e) 12.8g
Q18. At what temperature does 1 atm of N2(g) has the same density as 1 atm of the He(g) at
30°C?
a) 425 K b) 1981 K c) 2086 K d) 2121 K e) 430 K
1ST Semester 2023 / 2024
Hasan Shukri 33093777
Chemy 101
Q22. Which of the following statements regarding the colligative properties are true?
a) The vapor pressure of water over an aqueous solution of glucose is less than the
vapor pressure of pure water.
b) The boiling point of an aqueous solution of glucose is less than the boiling point
of pure water.
c) The freezing point of an aqueous solution of NaCl is less than the freezing point
of pure water.
d) The osmotic pressure of 0.1M aqueous solution of NaCl is more than that of 0.1M
aqueous solution of sugar, both at 25C.
Q23. a mixture of methane and helium is placed 2.0L flask at 27°C. The partial
pressure of CH4 is 0.37atm and partial pressure of helium is 0.23 atm what is the mole
fraction of CH4
a) 0.23 b) 0.29 c) 0.62 d) 0.77 e) 3.55
Q24. The density of a gas 1.80 g/L at 27°C and at 1.5 atm what will be the density at
STP
a) 1.82 g/L b) 1.94g/L c) 1.60 g/L d) 2.3g/L e) 1.32g/L
Q25. Water can decompose by electrolysis to hydrogen gas and oxygen gas. What
mass of water must decompose to yield 24.0L of oxygen 1.00 atm and 25°C ?
2H2O(l) → 2H2(g) + O2(g)
a) 35.3g b) 17.7g c) 23.6g d) 70.7g e) 11.1g
