Tag: chemistry

Quizzes (490) Questions (9892)

Questions Related to chemistry

Multiple choice chemistry materials liquid crystals liquid state the liquid state

What is the shape of the meniscus observed when water and mercury are taken in two different capillary tubes?

  1. Concave and convex

  2. Convex and concave

  3. Both concave

  4. Both conves
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The shape of the meniscus observed when water and mercury are taken in two different capillary tubes is concave and convex respectively.

Multiple choice chemistry materials liquid crystals liquid state the liquid state

The amount of energy required to change $1\ kg$ of a solid into liquid at atmospheric pressure at its melting point is known as _______________.

  1. latent heat of fusion

  2. latent heat of boiling

  3. latent heat of freezing

  4. melting energy
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
The amount of energy required to change $1\ kg$ of a solid into liquid at atmospheric pressure at its melting point is known as latent heat of fusion.

Hence option A is correct.

Multiple choice chemistry materials liquid crystals liquid state the liquid state

These two compounds are in the liquid phase at $293\ K$ :

  1. $Br _{2}$ and $Hg$
  2. $Cl _{2}$ and $F _{2}$
  3. $NH _{4}^{+}$ and $H _{3}O^{+}$
  4. $Fe$ and $Co$

  5. Diamond and graphite
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

$Br _2$ and $Hg$ are in the liquid phase at $293 :K$.
$Cl _2$ and $F _2$ are gases.
$NH _4^+$ and $H _3O^+$ exist in aqueous solution.
$Fe$ and $Co$ are solids
Diamond and graphite are also solids.

Multiple choice chemistry materials liquid crystals liquid state the liquid state

An experiment is conducted where droplets of liquid are placed on the surface of a penny. Which of the following substances would you expect to the able to place the maximum number of drops of on the surface of the penny?

  1. $HF$
  2. $H _{2}O$
  3. $CH _{3}CH _{2}CHO$
  4. $CCl _{4}$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Fluorine is most electronegative element so it forms stronger hydrogen bond which is the reason of stronger surface tension.So HF drops place maximum on the penny.

Multiple choice chemistry materials liquid crystals liquid state the liquid state

What happens to the rate of evaporation of water, if the atmospheric pressure is decreased during the extraction of colored components?

  1. Increases

  2. Decreases

  3. Do not change

  4. None
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The rate of evaporation of water increases, if the atmospheric pressure is decreased during the extraction of colored components because atmospheric pressure is inversely proportional to evaporation. 

Multiple choice chemistry materials liquid crystals liquid state the liquid state

What happens to the rate of evaporation of water, if the atmospheric pressure is increased during the extraction of the colored component from liquid? 

  1. Increases

  2. Decreases

  3. Do not change

  4. None
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Evaporation is a surface phenomenon in which surface molecules of solution moves to the atmosphere.If atmospheric pressure is increased then due to external pressure molecules on the surface will not move to the atmosphere so if atmospheric pressure increases, a rate of evaporation decreases.

Multiple choice chemistry materials liquid crystals liquid state the liquid state

The volume of gas is reduced to half from its original volume. The specific heat will be :

  1. reduce to half

  2. be doubled

  3. remain constant

  4. increase four times
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Specific heat capacity is an intensive property of a substance. It depends on the nature of the gas and the process (isobaric vs isochoric), not on the volume of the gas.

Multiple choice chemistry materials liquid crystals liquid state the liquid state

At high altitudes, water boils at a lower temperature because

  1. the atmospheric pressure is high at high altitudes

  2. the viscosity of water is reduced at high altitudes

  3. the atmospheric pressure is low at high altitudes

  4. the surface tension of water is reduced at high altitudes
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The boiling of water depends on the atmospheric pressure at that altitude. At high altitudes, the pressure is lower, so water can not boil at $100°$. As the altitude increases, the boiling point of water reduces.

Multiple choice chemistry materials liquid crystals liquid state the liquid state

Liquids are similar to gases because:

  1. both possess the property of flowing and take the volume of the containers

  2. both diffuse and take the shape of the containers

  3. both are readily compressible and diffuse

  4. both are capable of infinite expansion
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Liquids and gases are similar in both shape and volume because they both have its' shape determined by its' surroundings. 

$\Longrightarrow $ Both diffuses and take the shape of containers.