chapter 5 electrochemistry class 12 chemistry textbook solution
3. Answer the following in brief
iv. How many moles of electrons are passed when 0.8 ampere current is passed for 1 hour through molten CaCl2 ?
Answer:-
Given:
Current (\(I\)) = 0.8 ampere,
Time (\(t\)) = 1 hour = 1 \times 60 \times 60 s = 3600 s
To find:
Number of moles of electrons passed through molten CaCl₂
Formulae:
1. Quantity of electricity passed = \[I(\text{A}) \times t(\text{s})\]
2. Number of moles of electrons passed = \(\frac{Q(\text{C})}{96500 \left(\frac{\text{C}}{\text{mol}\, e^-}\right)}\)
Calculation:
Using formula (i),
Quantity of electricity passed = (\(I(\text{A}) \times t\(text{s}) = 0.8 \times 3600 \)
(\= 2880 \text{ C}\)
Using formula (ii),
Number of moles of electrons passed:
\[\frac{Q(\text{C})}{96500 \left(\frac{\text{C}}{\text{mol}\, e^-}\right)}\]
\[= \frac{2880 \text{ C}}{96500 \left(\frac{\text{C}}{\text{mol}\, e^-}\right)} \]
\[= 0.03 \text{ mol}\, e^-\]
Number of moles of electrons passed through molten CaCl₂ is 0.03 mol \(e^-\).
chapter 5 elctrochemistry textbook solution page 118