2006 - JAMB Chemistry Past Questions and Answers - page 5
41
In the electrolysis of CuSO4(g) using platinum electrodes, the reaction at the anode is
A
4H+ + 4e- → 2H2
B
4OH- - 4e- → 2H2O + O2
C
2OH - 2e- → 2OH
D
2OH- + 2OH- → 2H2O + O2
correct option: b
Users' Answers & Comments42
Na2CO3(g) + 2HCl(aq) → 2NaCl(aq) + H2O(l) + CO2(g)
How many moles of sodium trioxocarbonate (IV) are there in a 25 cm3 solution which required 10cm3 of 0.05 mol dm-3 hydrochloric acid solution to neutralize it?
How many moles of sodium trioxocarbonate (IV) are there in a 25 cm3 solution which required 10cm3 of 0.05 mol dm-3 hydrochloric acid solution to neutralize it?
A
1.000 mole
B
0.100 mole
C
0.010 mole`
D
0.111 mole
correct option: c
\(\frac{C_A V_A}{C_BV_B} = \frac{a}{b}\)
\(\frac{0.05 \times 10}{C_B \times 25} = \frac{2}{1}\)
50CB = 0.5
CB = \(\frac{0.5}{50} = \frac{5}{100}\)
= 0.01
Users' Answers & Comments\(\frac{0.05 \times 10}{C_B \times 25} = \frac{2}{1}\)
50CB = 0.5
CB = \(\frac{0.5}{50} = \frac{5}{100}\)
= 0.01
43
If the heat of combustion of hydrogen is -285.8kJ,
What is the heat of formation of water?
What is the heat of formation of water?
A
+571.6 kJ
B
-571.6 kJ
C
-285.8 kJ
D
+285.8 kJ
correct option: c
Users' Answers & Comments44
5SO2(g) + 2KMnO4(aq) + 2H2O(l) → K2SO4 + 2MnSO4(aq) + 2H2SO4(aq)
In the reaction above, the products give a
In the reaction above, the products give a
A
purple solution
B
purple precipitate
C
colourless precipitate
D
colourless solution
correct option: d
Users' Answers & Comments45
A
hydrogen
B
chlorine
C
oxygen
D
hydrogen chloride
correct option: c
Users' Answers & Comments46
A
NH4NO3(s) + CaSO4(s),/sub>
B
NH4CL(s) + NaNO2(s)
C
NH4NO2(s) + Na2SO4(s)
D
NH4CL(s) + Ca(OH)2(s)
correct option: d
Users' Answers & Comments47
A
2-butanone
B
2-butanal
C
3-butanal
D
3-butanone
correct option: a
Users' Answers & Comments
49
A
A
B
B
C
C
D
D
correct option: b
Users' Answers & Comments