Question

When the alcohol thermometer is placed in 20∘c water, what temperature will the thermometer record?

Answer 1

When an alcohol thermometer is placed in $20{\text{ }}^\circ {\text{C}}$ water, the thermometer will record temperature $\boxed{{\text{greater than }}20{\text{ }}^\circ {\text{C}}}$.

Further explanation:

Temperature:

It is a physical quantity that measures the hotness or coldness of any substance. It is an intensive property. The device used to measure temperature is a thermometer. Three common scales are there to measure the temperature of a substance. These are the Celsius scale, Kelvin scale, and Fahrenheit scale. SI unit of temperature is Kelvin (K).

An alcohol thermometer is a substitute for mercury thermometers. It is an equipment that is used to measure the temperature of any object. The alcohol thermometer has less toxic contents as compared to those present in mercury thermometer.

Thermal expansion arises when there is change in the size and shape of the substance with a change in temperature.

Volume expansion occurs when a substance is expanded in three-dimensional space. The expression for volume expansion is as follows:

$\Delta V = {V_0}\beta \Delta T$         …… (1)                                      

Here,

$\Delta V$ is the change in volume.

${V_0}$ is the initial volume.

$\beta$ is the coefficient of volume expansion.

$\Delta T$ is the temperature change.

Rearrange equation (1) for $\Delta T$.

 $\Delta T =\dfrac{{\Delta V}}{{{V_0}\beta }}$   …… (2)                                            

The change in temperature is inversely related to the coefficient of volume expansion. The value of $\beta$ for mercury is $1.82\times10^{-4}\ \ ^{\circ}\text{C}^{-1}$ and that for alcohol is $1.12 \times {10^{ - 4}}{\text{ }}^\circ {{\text{C}}^{ - 1}}$. So the temperature recorded by the alcohol thermometer will be greater than $20{\text{ }}^\circ {\text{C}}$.

Learn more:

1. Which of these is an extensive property? brainly.com/question/1398514

2. Which of the phase changes is an exothermic change? brainly.com/question/1875234

Answer details:

Grade: Senior School

Subject: Chemistry

Chapter: Thermodynamics

Keywords: temperature, alcohol thermometer, hotness, coldness, intensive, extensive, thermal expansion, volume expansion.

Answer 2

The thermometer operates under the concept of the Zeroth Law of Thermodynamics. The thermometer displays the temperature of its surroundings, regardless of the identity of the substance. So, if the water is 20°C, then the thermometer displays 20°C.