Class 6 Science Chapter 4 MCQ

Materials are grouped together on the basis of similarities and differences in their properties. In everyday life, we often group materials for our convenience.

In solids, particles are tightly packed. In liquids the space of particles is larger than solids but smaller than gases. The space between particles is maximum in gases. Generally, they are loosely packed.

The term “combustibility” refers to the tendency of a substance to burn as a result of fire or chemical reaction. It is can be expressed as a property that is a measure of how easily a substance will ignite or burn.

Cotton ball initially floats on water but after few minutes it sinks because it absorbs water. All the materials, which are lighter than water, float on water. Wood piece does not sink in any circumstances. Here option [C] will be your answer. So, don’t be confused.

In solids, particles are tightly packed. In liquids the space of particles is larger than solids but smaller than gases. The space between particles is maximum in gases. Generally, they are loosely packed. Hence, intermolecular force attraction found strongest in solids, weaker in liquids and weakest in gases.

All are rounded eatable objects, except basket-ball. Hence, option [D] will be your answer.

Among of these, here graphite (non-metal) is a good conductor of heat.

The materials which allow heat to pass through them easily are “conductors” of heat. For examples, aluminum, iron and copper. The materials which do not allow heat to pass through them easily are poor conductors of heat such as plastic and wood. Poor conductors are known as “insulators”.

We know that some materials are hard, lustrous, malleable, ductile, sonorous and good conductors of heat and electricity, called metal. Iron is very hard and strong metal and it is found everywhere and relatively cheaper than any other metals. Therefore, we use an iron metal or rod in window as well as door lock.

Water is a conductor of electricity. Pure water is actually a good insulator. Tap water can be a good conductor due to calcium, magnesium, and carbonate ions, or other substances. Any impurities, like salts, in the water enable it to conduct electricity. Pure water does not conduct electricity. This is because pure water do not contain any salts or components.