Tag: the kinetic model of matter

Quizzes (2) Questions (93)

Questions Related to the kinetic model of matter

Multiple choice physics the kinetic model of matter force and kinetic theory change of states phase change

If, melting and boiling point of a liquid is $-{50}^{o}C$ and ${150}^{o}C$ respectively, and on the basis of this liquid a thermometer is formed with ${0}^{o}L$ representing the melting point as the minimum temperature on the scale and ${100}^{o}L$ representing the boiling point as the maximum temperature on the scale, find the melting and boiling point on this thermometer

  1. $0$ and ${100}^{o}L$ respectively

  2. ${30}^{o}L$ and ${80}^{o}L$ respectively

  3. ${20}^{o}L$ and ${70}^{o}L$ respectively

  4. ${25}^{o}L$ and ${75}^{o}L$ respectively
Reveal answer Fill a bubble to check yourself
D Correct answer
Multiple choice physics the kinetic model of matter force and kinetic theory change of states phase change

The saturated vapour pressure of water at $100^\circ C$ is

  1. 750 mm of Hg

  2. 760 mm of Hg

  3. 76 mm of Hg

  4. 7.6 cm of Hg
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Vapour pressure or equilibrium vapour pressure or saturated vapour pressure is defined as the pressure exerted by a vapour in thermodynamic equilibrium with condensed phase at given temperature. At $100^oC$, the vapour pressure is $1atm$; i.e. 760mm of Hg i.e. 76cm of Hg as $1mm=10^{-1}cm$.

Multiple choice physics the kinetic model of matter force and kinetic theory change of states phase change

The water can be made to boil even at $0$ if the pressure of surrounding is:

  1. 56 cm of Hg

  2. 5 cm of Hg

  3. 0.1 cm of Hg

  4. 4.6 mm of Hg
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
The water can be made to boil even at $0^\circ C$. 
As we know, the ideal equation for gases is $pV=nRT$. Now, if $V$ and $n$ are taken constants, $p=cT$, where $c$ is a constant.
So pressure is directly proportional to the temperature.
Water boils at $100^\circ C$ or $373K$ at $1atm$ pressure. So, to obtain boiling at $0^\circ C$ or $273K$, you need to reduce the pressure to $\dfrac {273\times 1}{373} atm = 0.732 atm=56\text{cm of Hg}$(approx).
Multiple choice physics the kinetic model of matter force and kinetic theory change of states phase change

When 1 g of water at $100^\circ C$ gets converted into steam at the same temperature, the change in volume is approximately

  1. 1 cc

  2. 1000 cc

  3. 1500 cc

  4. 1670 cc
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

During change of state mass does not change.

Mass of water = 1gm
So mass of steam is also= 1gm
Density of steam =$0.0006gm/cm^3$
Initail volume of water =1$cm^3$(Density =$1gm/cm^3$) ($1=\dfrac { 1 }{ V } $) $,v=1cm^3$
Later volume of water converted to steam =$\dfrac { mass\quad of\quad steam }{ Density\quad of\quad steam } $
$=\dfrac { 1 }{ 0.0006 } $
$=\dfrac { 10000 }{ 6 } { cm }^{ 3 }$
$= 1670cm^3$
Change of volume = $1670cm^3$