Phase Transitions | MCQs

Explanation

Explanation

Evaporation is the process where liquid turns into gas at temperatures below its boiling point.

It occurs at the surface of the liquid.

It is influenced by factors like temperature and surface area.

Explanation

The melting point of ice at normal atmospheric pressure is 0 °C (zero degrees Celsius).

Key Points:

• 0 K (zero Kelvin) is equivalent to -273.15 °C, which is absolute zero, the lowest possible temperature.
• 100 °C is the boiling point of water at normal atmospheric pressure.

Explanation

• Sublimation is the transition of a substance from the solid to the gas phase without going through the liquid phase.
• Glucose and Sodium Chloride do not sublime, as they require a liquid phase transition before turning into a gas.

Here are the some solid sublime material:

• Iodine
• Camphor or Dry ice

Explanation

Tin has the lowest melting point (~232°C) among.

• Zinc (~419°C)
• Gold (~1064°C)
• Lead (~327°C)

Explanation

• Freezing is the process by which a liquid changes to a solid.
• It is the reverse of melting, which is the process by which a solid changes to a liquid.

Explanation

• A change in physical appearance or state of a substance, such as a change in shape, size, color, or phase (solid, liquid, gas), is called a Physical Change.
  

The are examples of Physical Changes:

• Melting (ice cream, wax, chocolate, ice and change from solid to liquid)
• Phase changes (boiling, freezing, condensation)
• Crushing (chalk)
• Tearing (paper)
• Crumpling (aluminium foil)
• Stretching (rubber band)
• Mixing (sugar in water)
• Dissolving (sugar, salt in water)
• Moulding (clay, metals)
• Slicing (fruit)
• Forming of frost (from water vapors)
• Transition to a gas (change from liquid to gas)
• Change of durability (change in texture or strength)
• Changes to crystal form (change in crystal structure)

Explanation

A change in physical appearance or state of a substance, such as a change in shape, size, color, or phase (solid, liquid, gas), is called a Physical Change.

Explanation

• A release of gas is typically a sign of a chemical change, not a physical change.

The signs of physical change:

• Change that can be reversed
• The substance does not turn into a new substance

Explanation

• Sublimation is the transition of a substance from the solid to the gas phase without going through the liquid phase.
• This means that a solid changes directly into a gas, without first melting into a liquid.