Tutorial 3 1 
UNIVERSITI TUNKU ABDUL RAHMAN
Centre
Course
Year/
Trimester
Lecturer
:
:
:
Centre for Foundation Studies
Foundation In Science
Year 1 Trimester 1
Unit Code
Unit Title
Session
:
:
:
FHSC1114
Physical Chemistry
2015/05
:
Ms. Amelia Chiang, Ms. Azlina Banu, Ms. Farhanah, Ms.Gurpreet, Ms. Jamie, Ms.
Lau Mei Chien, Ms. Lily Lee, Ms. Nabilah, Mr. Ng Sweet Kin, Ms. Phang Ying Ning,
Ms. Precilla, Ms. Rachel Tham, Ms. Rajalakshmi, Mr. Sivabalan, Ms. Tan Lee Siew
Tutorial 3: Chapter 3 Stoichiometry and Solution Concentration
1.
Balance the following equations:
(a)
(b)
2.
V2O5(s) + CaS(s) CaO(s) + V2S5(s)
GaBr3(aq) + Na2SO3(aq) Ga2(SO3)3(aq) + NaBr(aq)
316.0 g of aluminum sulfide, Al2S3 reacts with 493.0 g of water, H2O. Given the unbalanced equation as below:
Al2S3(s) + H2O(l) → Al(OH)3(s) + H2S(g)
(a)
Find the excess reactant.
(Ans: H2O)
(b)
Find the mole of the excess reactant that remains after the reaction. (Ans: 14.742 mole)
[Sep 2014]
3.
Consider the reaction below:
2Al(s) + 3I2(s) 2AlI3(s)
(a)
Determine the limiting reagent and the theoretical yield of the product if 1.20 moles of aluminium and 2.40 moles of iodine are used.
(Ans: 489.218 g)
(b)
Calculate the percentage yield of the product if 450 g of AlI3 is obtained.
(Ans: 91.98%)
4.
A salt solution is produced when 2.9 g of sodium chloride, NaCl dissolved in 200 ml of water.
Calculate the molality (m) of the NaCl solution, given that the density of water is 1.00 g ml⁻1.
(Ans: 0.25 m)
[Apr 2013]
1
5.
Carbon and hydrogen atoms make up a compound which yields 0.345 g of carbon dioxide and
0.153 g of water vapour when burnt in air. Determine the empirical formula of the compound.
(Ans: CH2)
6.
A fuel mixture used in the early days of rocketry is composed of two liquids, hydrazine, N2H4, and dinitrogen tetraoxide, N2O4, which ignite on contact to form nitrogen gas and water vapor.
Calculate the mass of nitrogen gas formed when 100 g of N2H4 and 200 g of N2O4 are mixed.
(Ans: 131.148
Centre
Course
Year/
Trimester
Lecturer
:
:
:
Centre for Foundation Studies
Foundation In Science
Year 1 Trimester 1
Unit Code
Unit Title
Session
:
:
:
FHSC1114
Physical Chemistry
2015/05
:
Ms. Amelia Chiang, Ms. Azlina Banu, Ms. Farhanah, Ms.Gurpreet, Ms. Jamie, Ms.
Lau Mei Chien, Ms. Lily Lee, Ms. Nabilah, Mr. Ng Sweet Kin, Ms. Phang Ying Ning,
Ms. Precilla, Ms. Rachel Tham, Ms. Rajalakshmi, Mr. Sivabalan, Ms. Tan Lee Siew
Tutorial 3: Chapter 3 Stoichiometry and Solution Concentration
1.
Balance the following equations:
(a)
(b)
2.
V2O5(s) + CaS(s) CaO(s) + V2S5(s)
GaBr3(aq) + Na2SO3(aq) Ga2(SO3)3(aq) + NaBr(aq)
316.0 g of aluminum sulfide, Al2S3 reacts with 493.0 g of water, H2O. Given the unbalanced equation as below:
Al2S3(s) + H2O(l) → Al(OH)3(s) + H2S(g)
(a)
Find the excess reactant.
(Ans: H2O)
(b)
Find the mole of the excess reactant that remains after the reaction. (Ans: 14.742 mole)
[Sep 2014]
3.
Consider the reaction below:
2Al(s) + 3I2(s) 2AlI3(s)
(a)
Determine the limiting reagent and the theoretical yield of the product if 1.20 moles of aluminium and 2.40 moles of iodine are used.
(Ans: 489.218 g)
(b)
Calculate the percentage yield of the product if 450 g of AlI3 is obtained.
(Ans: 91.98%)
4.
A salt solution is produced when 2.9 g of sodium chloride, NaCl dissolved in 200 ml of water.
Calculate the molality (m) of the NaCl solution, given that the density of water is 1.00 g ml⁻1.
(Ans: 0.25 m)
[Apr 2013]
1
5.
Carbon and hydrogen atoms make up a compound which yields 0.345 g of carbon dioxide and
0.153 g of water vapour when burnt in air. Determine the empirical formula of the compound.
(Ans: CH2)
6.
A fuel mixture used in the early days of rocketry is composed of two liquids, hydrazine, N2H4, and dinitrogen tetraoxide, N2O4, which ignite on contact to form nitrogen gas and water vapor.
Calculate the mass of nitrogen gas formed when 100 g of N2H4 and 200 g of N2O4 are mixed.
(Ans: 131.148