Test: Matter In Our Surroundings (Medium) - Class 9 MCQ

As Meena pushes the bottle, the water level in the bottle increases and air present in the bottle gets pushed into the tube, which is bubbled out from the beaker. This experiment proves that air and water occupy some space, and only one matter can occupy space at any time.

The fraction of solute present in water as temperature concentration in water will decrease; hence, the fraction of solute present in water changes.

The matter is affected by the inertia. Inertia is the tendency of the matter to be in a state of rest or motion. Example: The book on the desk remains in rest position utilities picked up from the desk. Thus It Is Showing Inertia.

The water kept in an earthen pot main cool even in summer because of the earthen pot as many small holes. Water seeps out through them and evaporates from the surface of the pot. The energy needed for evaporation is taken from the water kept in the earthen pot. As a result, water kept in earthen pot become cool.

If the tube has been open on both sides, the mercury will fall, so that is not the case. Also, the pressure will increase slightly because of the weight of mercury. So the tube must be closed at both the ends.

On the increasing temperature, the diffusion rate increases as the kinetic energy of matter increases and more intermixing of matter occurs.

Intermolecular spaces in water, steam, and ice:
- Intermolecular space refers to the distance between molecules within a substance. It determines the density and physical properties of the substance.
- Water exists in three states: solid (ice), liquid (water), and gas (steam). Each state has different intermolecular spaces.
Explanation:
- In the case of water, the intermolecular space is the least among the three states.
- Water molecules in the liquid state are in close proximity to each other, forming hydrogen bonds. This results in a relatively small intermolecular space.
- In ice, the water molecules arrange themselves in a regular pattern, forming a crystal lattice structure. This structure causes the molecules to be further apart compared to the liquid state. Therefore, the intermolecular space in ice is greater than in liquid water.
- Steam, being the gaseous state of water, has the largest intermolecular space. The water molecules are far apart and move freely, resulting in a larger distance between them.
Summary:
- The intermolecular space is the least in water (liquid state) because the molecules are in close proximity due to hydrogen bonding.
- Ice has a greater intermolecular space compared to water due to the regular arrangement of water molecules in a crystal lattice.
- Steam has the largest intermolecular space as the water molecules are far apart and freely moving in the gaseous state.

When Venu blows the straw, he applies pressure by pushing air into which form air bubbles water, the pressure in the basin increases and the water level in the beaker increases.The air bubbles formed in the water escape into the beaker.

A volatile liquid one that evaporates or evaporates quickly at room temperature. Volatile Liquids Have a low boiling point. As a result, they evaporate very easily at room temperature.

Evaporation is the process of a substance in a liquid state changing to a gaseous state due to an increase in temperature and/or pressure. Evaporation is a fundamental part of the water cycle and is constantly occurring throughout nature.

Water freezes at temperatures below 273 kelvins. Water boils at 373 kelvins. ... The "size" of a one-degree change in temperature is the same in the Celsius and Kelvin scales, so the freezing point of water is at a temperature of 273.15 kelvins (that is, 273.15 degrees above absolute zero).

The earthen pot and water hence lose heat, making the water inside the pot cool. This evaporation of water produces a cooling effect. Some of the heat energy that is generated is used in the process of evaporation. Hence, water stored in earthen pots tends to become cooler in summer.

Increasing the temperature of a body of water also often increases evaporation. This is because as the temperature rises, the water molecules begin moving about more rapidly. This increases the odds that molecules will escape.

Temperature of the water during vaporization does not change because the heat is used in overcoming particle-particle attraction forces, which keeps the temperature constant.

On increasing pressure, the volume of the gas decreases which brings gaseous molecules together and decreases the space between them and on decreasing the temperature the kinetic energy of the molecules decreases and forces of attraction between them increases and thus, gas can be converted into liquid.

273 + 100 = 373 K.

Particles in a gas are well separated with no regular arrangement. Liquids are close together with no regular arrangement. Solids are tightly packed, usually in a regular pattern.

When water solidifies to ice, heat is liberated into surroundings. Reason: The process of converting liquid to ice is called freezing. During freezing, the energy lost by water molecules is gained by the surrounding molecules.

Generally, when temperature and humidity are constant, and wind speed increases, the evaporation rate increases as well. When temperature and wind speed are constant, but humidity increases, the rate of evaporation will decrease.

The motion particles in steam are fastest. And the energy due to virtue of motion of particles is Kinetic energy. water uses the heat and forms steam ice is in solid phase thus no motion in particles water is a liquid in which has the slower speed of particles than of gas like steam