Primary Cells

Q.

Write the chemistry of recharging the lead storage battery, highlighting all the materials that are involved during recharging.

Q. The standard electrode potential of $C{u}^{2+}/Cu$ is $+0.34\text{V}$. At what concentration of $C{u}^{2+}$ ions will this electrode potential be zero?

Take:
$Antilog(-11.52)=3\times {10}^{-12}$

1. $\left[C{u}^{2+}\right]=3.01\times {10}^{-12}\text{M}$
2. $\left[C{u}^{2+}\right]=0.5\times {10}^{-12}\text{M}$
3. $\left[C{u}^{2+}\right]=3.01\times {10}^{-5}\text{M}$
4. $\left[C{u}^{2+}\right]=1.5\times {10}^{-5}\text{M}$

Q.

What is the potential of a dry cell?

Q.

The dry cell is also known as:

Q.

What is the EMF of a dry cell?

Q.

Can zinc-carbon batteries be recharged?

Q.

A depolarizer used in dry cell is

1. Ammonium chloride

2. Manganese dioxide

3. Potassium oxide

4. Sodium phosphate

Q.

Which cell is used to convert the chemical energy of H₂ gas into electrical energy?

1. Electrolytic cell

2. Fuel cell

3. Discharge cell

4. Electrochemical cell

Q.

In an electrochemical cell, the function of salt bridge is:

1. It allows solutions to move from one half cell to the other half cell

2. It only allows ions to move from anode to cathode

3. It keeps the level of solutions same

4. It allows the current to flow through the cell and keep solutions electrically neutral

Q.

The combination of two or more cells is called a ________.

Q.

A group of two or more cells is called a________.

Q. A depolariser used in dry cell batteries is:

1. sodium phosphate
2. ammonium chloride
3. manganese dioxide
4. potassium hydroxide

Q. Which of the following statement(s) is/are true about secondary batteries?

1. It can be recharged
2. It cannot be reused
3. Act as galvanic cell during discharge
4. Act as electrolytic cell during charging

Q.

How can you tell if a Battery is dry ?

Q.

Which of the following cells can be recharged?

1. Edison Cell

2. Lead Storage Cell

3. Nickel Cadmium Cell

4. All of the above

Q. The standard electrode potential of $C{u}^{2+}/Cu$ is $+0.34\text{V}$. At what concentration of $C{u}^{2+}$ ions will this electrode potential be zero?

Take:
$Antilog(-11.52)=3\times {10}^{-12}$

1. $\left[C{u}^{2+}\right]=0.5\times {10}^{-12}\text{M}$
2. $\left[C{u}^{2+}\right]=1.5\times {10}^{-5}\text{M}$
3. $\left[C{u}^{2+}\right]=3.01\times {10}^{-5}\text{M}$
4. $\left[C{u}^{2+}\right]=3.01\times {10}^{-12}\text{M}$

Q. Which of the following statement is incorrect about secondary batteries?

1. It can be recharged
2. It cannot be reused
3. Act as galvanic cell during discharge
4. Act as electrolytic cell during charging

Q.

A cell converts ……………….. (electrical/chemical) energy into ………………. (electric/chemical) energy.

Q.

(a) What should be the physical state of Lead bromide if it is to conduct current?

(b) What particles are present in pure Lead bromide?

(c) Write the equations for the reactions which take place at electrodes during the electrolysis of Lead bromide.

Q.

What is a secondary cell?

Q. A cell contains two hydrogen electrode. The negative electrode is in contact with a solution of ${10}^{-6}M$ hydrogen ions. The emf of the cell is $0.118$ volt at ${25}^{\circ }C$. Calculate the concentration of hydrogen ions at the positive electrode.

Q. Assertion: Dry cell is a primary cell and lead storage cell is a secondary cell.
Reason: A primary cell can only be used once while secondary cells are rechargeable.

1. Both Assertion and Reason are true and Reason is the correct explanation of Assertion
2. Assertion is false but Reason is true
3. Both Assertion and Reason are true but Reason is not the correct explanation of Assertion
   
4. Both Assertion and Reason are false
5. Assertion is true but Reason is false

Q.

Difference between cell and battery.

Q. What is a secondary cell?

Q. Rancho being a curious boy and a lover of chemistry wanted to know about the working of this clock battery. He read about it and came to some conclusions. Which of these Rancho’s conclusion are TRUE?

1. Graphite rod acts as the anode.
2. The Zinc container as the cathode.
3. At anode: $Zn\left(s\right)\to Z{n}^{2+}\left(aq\right)+2e^{-}$
4. At cathode: $Mn{O}_2+N{H}_4^{+}+e^{-}\to MnO\left(OH\right)+N{H}_3$

Q.

Consider the cell reaction:
Cd(s) | Cd²⁺ (1.0 M) || Cu²⁺ (1.0 m) | Cu (s)
If we wish to make a cell with more positive voltage using the same substances, we should:

1. Increase [Cd²⁺] as well as [Cu²⁺] to 2.0 M

2. Reduce only [Cd²⁺] to 0.1 M

3. Decrease [Cd²⁺] as well as [Cu²⁺] to 0.1 M

4. Increase only [Cu²⁺] to 2.0 M

Q. Tungsten is a metal used in the filament of incandescent bulbs. What is the chemical symbol of Tungsten?

1. W
2. Tn
3. Tu
4. Wo

Q. A secondary cell is one that :

1. can be recharged by passing current through it in the opposite direction
2. can be recharged
3. can be recharged by passing current through it in the same direction
4. can not be recharged

Q. Which colorless gas evolves, when $N{H}_{4}Cl$ reacts with zinc in a dry cell battery

1. NH₄
2. N₂
3. H₂
4. Cl₂

Q. Now Rancho started opening up batteries in different objects. He opened battery of his watch now. After opening it up, he made some observations. Which of the following observations of Rancho are TRUE?

1. It is a Zn – Carbon dry cell.
2. It consists of zinc container as the anode.
3. It consists of a carbon rod as the cathode.
4. Moist mercuric oxide with KOH is filled between the two electrodes.