Single Choice

When an electric current is passed through acidified water, $$112$$ mL of hydrogen gas at N.T.P. was collected at the cathode in $$965$$ seconds. The current passed, in ampere, is _______.

A$$0.1$$
B$$2.0$$
C$$1.0$$
Correct Answer
D$$0.5$$

Solution

Reduction at cathode: $$2 H^+(aq) + 2e^- \rightarrow H_2(g)$$
At N.T.P, 22.4 L (or 22400 mL) of $$H_2=$$ 1 mole of $$H_2$$
$$112$$ mL of $$H_2= \dfrac {112}{22400} \times 1=0.005$$ mole of $$H_2$$
Moles of $$H_2$$ produced $$= \dfrac {I(A) \times t(s)}{96500 (C/mole^-)} \times $$ mole ratio
$$0.005 mol= \dfrac {I(A) \times 965s}{96500 (C/mole^-)} \times \dfrac {\text { 1 mol } H_2}{\text { 2 mol } e^-} $$
$$ I= 1 \: A$$

SIMILAR QUESTIONS

Electrochemistry

A copper voltameter, a silver voltameter and a water voltameter are connected in series and current is passed through them for some time. The ratio of the number of moles of copper, silver and hydrogen formed at the cathode is:

Electrochemistry

The number of faradays required to liberate 1 mole of any element indicates :

Electrochemistry

Number of electrons required to deposit one mole of $$Mg^{2+}$$ ion is :

Electrochemistry

The anodic half-cell of lead-acid battery is recharged unsing electricity of $$0.05$$ Faraday. The amount of $$PbSO_4$$ electrolyzed in g during the process is : $$($$ Molar mass of $$PbSO_4 = 303 g mol^{-1}) $$

Electrochemistry

How long (approximate) should water be electrolysed by passing through 100 amperes current so that the oxygen released can completely burn $$27.66\, g$$ of diborane? (Atomic weight of $$B=10.8 u$$)

Electrochemistry

If three faradays of electricity is passed through the solution of $$AgNO_3, CuSO_4$$ and $$AuCl_3$$, the molar ratio of the cations deposited at the cathodes will be:

Electrochemistry

What will be the volume of $$O_2$$ at N.T.P liberated by $$5$$ A current flowing for $$193$$ s through acidulated water?

Electrochemistry

During the electrolysis of molten sodium chloride, the time required to produce 0.10 mol of chlorine gas using a current of 3 amperes is:

Electrochemistry

The number of electrons delivered at the cathode during electrolysis by a current of 1 ampere in 60 seconds is : (charge on an electron is $$1.60 \times 10^{-19}C)$$ :

Electrochemistry

The number of Faradays(F) required to produce $$20 g$$ of calcium from molten $$CaCl_2$$ (Atomic mass of $$Ca = 40 g\ mol^{-1})$$ is

Contact Details