5
15
25
35
50
Correct answer is C
CaCO3 + CaO \(\to\) 2CaO + 2CO2
44gm of CO3 is liberated by 100gm of CaCO3
0.33gm of CO2 will be liberated by \(\frac{100}{44}\) x 0.33
= 0.75 of CaCO3
Amount of CaO = 1 - 0.75
= 0.25
% of CaO = \(\frac{0.25}{1} \times \frac{100}{1}\)
= 25%
0.54g
1.08g
1.62g
2.16g
3.24g
Correct answer is D
Same period, Same current
\(Cu^{2+} + 2e^- → Cu; 2Ag^+ + 2e^-\) → Ag
From the equation above, 2 mol Ag ≡ 1 mol Cu
But 0.63g Cu = \(\frac{0.63}{63}\) = 0.01mole Cu
Hence 0.002 mole Ag is deposited
mass of Ag deposited = 0.002 x 108 = 2.16g.
In the above experiment, the litmus paper will initially
be bleached
turn green
turn red
turn blue
turn black
Correct answer is D
No explanation has been provided for this answer.
0.457g
0.500g
0.882g
0.914g
1.00g
Correct answer is A
Time = 2hrs = 120mins = 120 x 60secs =7200secs.
current = 0.193amps
Quantity of electricity = 7200 x 0.193 = 1389.6
2 x 96,500 deposits 63.5 gms of Cu
1389.6 will deposit \(\frac{63.5 \times 1389.6}{2 \times 96500}\)
= 0.457g
purer than sample 2
slightly denser than sample 2
in all respects the same as sample 2
colourless but sample 2 has a light brown colour
slightly less reactive than sample 2
Correct answer is B
No explanation has been provided for this answer.
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