Post on 21-May-2015
ANSWER ALL QUESTIONS
1. (a)
(b)
(c)
What is meat by the order of reaction?
A series of experiments was conducted to determine the rate of
formation of nitrogen gas; the product of the reaction between nitrogen
monoxide gas and hydrogen gas. The results obtained are tabulated as
follows:
Specify the orders of reaction with respect to NO and H2.
Write the rate equation and calculate the rate constant.
No. expt.
Concentration (mol dm3) Formation rate of N2 (mol dm3 s1) [NO] [H2]
1 4.0x103 1.0x103 5.67 x 103
2 4.0x103 2.0x103 11.54 x 103 3 1.0x103 4.0x103 0.96 x 103
Chemistry Unit
Session 2013/2014
Semester 2
Sample QUIZ Paper
NAME : ________________________________________________
MATRIC NUMBER : ________________________________________________
CLASS : ________________________________________________
NAME OF TUTOR : _____________________________________________
Solution: (a) Order of reaction is the power of reactants concentration in the rate law
equation.
(b) Order of reaction is obtain from experimental data.
Let rate laws , Rate = K[NO]x[H2]y where, K = rate constant
x is order with respect to NO
y is order with respect to H2
Order of reaction with respect to H2:
y
2
x
y
2
x
]H[]NO[K
]H[]NO[K
1rate
2rate
y33
y3x3
3
3
)101)(104(K
)102()104(K
1067.5
1054.11
21 = 2y
y = 1 Order of reaction with respect to NO:
y3x3
y3x3
)104()101(K
)102()104(K
3rate
2rate
x3
3
3
)104(5.01096.0
1045.11
x = 2.3 x 2
(c) Rate laws; Rate = K[NO]2[H2]1
Rate 1 = 5.67 10-3 = K(4 10-3)2 (110-3)
K = 3.2 105 M-2 s-1