States of Matter

Acetic acid is not a mixture. It is a compound.

Alcohol in water forms a homogeneous mixture. All others are heterogeneous mixtures.

Starch has carbon, hydrogen and oxygen as its constituents. Option (1) is the property of carbon. Option (2) is the property of oxygen and hydrogen. Option (3) is the property of sugar, not its constituents. Option (4) is the property of oxygen and hydrogen.

Charcoal and sulphur form a heterogeneous mixture.

Potable water should not be full of micro-organisms. It should be free of micro-organisms.

The viscosity of a fluid is a measure of its resistance to gradual deformation by shear stress or tensile stress. For liquids, it corresponds to the informal notion of thickness.

An isothermal process is a change of a system, in which the temperature remains constant: ΔT = 0. This typically occurs when a system is in contact with an outside thermal reservoir (heat bath), and the change occurs slowly enough to allow the system to continually adjust to the temperature of the reservoir through heat exchange.

Heat capacity or thermal capacity, is the measurable physical quantity that specifies the amount of heat required to change the temperature of an object or body by a given amount.

Blood agar is both differential and enriched medium. The blood that is incorporated into this medium is an enrichment ingredient for the cultivation of fastidious organisms such as the Streptococcus species. Chocolate agar is enriched culture media commonly used for primary isolation of Haemophilus species from clinical specimens.

Matter generally exists in three states; solid, liquid and gas. In solids, the particles are very close to each other and they have very strong inter-particle forces of attraction between them. 

Option (3) is correct.

100^oC is the boiling point of water, i.e. it is the temperature at which liquid starts boiling at the atmospheric pressure. Therefore, at this temperature both liquid and gaseous states of water can co–exist. Once boiling point is reached, the temperature of the system will remain constant until all water changes to gaseous state because the heat supplied is used to overcome the forces of attraction between particles of water so as to change it into gaseous state. At 99^oC, water will exist in liquid and at 101^oC, water will exist in gaseous state. At 0^oC (i.e. Melting point of ice) both ice and water will co-exist as at this temperature, ice starts melting. The heat supplied is used to overcome the forces of attraction between the particles so as to convert it into liquid state. The temperature will remain 0^oC until all the ice changes into liquid and therefore, at 0^oC, both solid and liquid states will co-exist.

When we pour some acetone (nail polish remover) on our palm, we feel cool. This is because particles gain energy (equal to latent heat of vapourisation) from our palm or surroundings and evaporate, causing the palm to feel cool. the palm will not get heated. It will not become red and it will not pain as nail polish remover does not harm our skin.

In water, evaporation takes place the slowest.