Q21.77P - Chemistry: Molecular Nature Of Matter And Change

Question

Many common electrical devices require the use of more than one battery. 

(a) How many alkaline batteries must be placed in series to light a flash light with a 6.0-V bulb? 

(b) What is the voltage requirement of a camera that uses six silver batteries?

 (c) How many volts can a car battery deliver if two of its anode/cathode cells are shorted?

Step-by-Step Solution

Answer

a. 4 alkaline batteries are required to light a flash light.

b. The voltage requirement of a camera is $9.6 \text{V.}$.

c. The car battery delivers $8 \text{V}$.

To find the alkaline batteries

a.

The average voltage of an alkaline battery is 1.5 V. To compute the number of batteries in series needed to light a flashlight with a 6.0 V -bulb, divide the required voltage by the average voltage of one battery.

$6.0 V\times \frac{1 battery}{1.5 V}=4 batteries$.

Hence, 4 alkaline batteries must be placed in series to light a flash light with a 6.0-V bulb

To find the voltage requirement

b.

The average voltage of a silver battery is 1.60 V. To get the voltage requirement of a camera, multiply the voltage of one battery by the number of batteries needed for the camera.

Number of batteries required are 6.

$$\begin{gathered} \text{Total} \text{voltage} =6.0\text{ batteries }\times \frac{1.60 \text{V}}{1\text{ battery }} \\ =9.6 \text{V} \end{gathered}$$

Hence the voltage requirement of a camera is 9.6V.

To find the volts

c.

A standard car battery has consisting of 6 cells with 2.0 V each. Given that two of the anode/cathode cells are shorted, only 4 cells remain functional. To get the voltage of the car battery,  the voltage produced per cell must be multiplied by the number of working cells left.

$$\begin{gathered} \text{Total} \text{voltage}=4\text{cells}\times \frac{2.0 \text{V}}{1\text{cell}} \\ =8.0 \text{V} \end{gathered}$$

Hence the car battery delivers 8V.