Elements, Compounds and Mixtures Test - 6

It is a Compound. Any substance that can be divided further into simpler substances is said to be a compound.

Therefore, option (a) is correct.

Brass is an alloy of copper and zinc, in proportions which can be varied to achieve varying mechanical and electrical properties. It is a substitutional alloy atoms of the two constituents may replace each other within the same crystal structure.

Therefore, option (b) is correct.

Matter is a substance that has inertia and occupies physical space. According to modern physics, matter consists of various types of particles, each with mass and size.

Therefore, option (a) is correct.

The simple, fundamental unit of an element is its atom. An element like helium, neon, argon etc. already have this octet of electrons, so they are stable as they are. So, they don't combine with other atoms; so these elements (inert gases) exist as atoms.

Therefore, option (b) is correct.

Liquefied petroleum gas is used for cooking food at the homes.

Hence the option C is correct.

Physical properties are those that can be observed or measured without changing the composition or identity of the substance. These properties include color, odor, taste, density, melting point, boiling point, conductivity, and hardness.

Therefore, option (a) is correct.

A mixture is defined as an impure substance made up of two or more types of elements (atoms) or compounds or both mechanically mixed in any proportion, and it can be further subdivided into simpler substances by physical (mechanical) means.

Therefore, option (a) is correct.

Sodium is an element that is a member of the alkali metal group with a symbol Na. It is physically silver colored and is a soft metal of low density. When an element is oxidized to its most common oxide and dissolved in water the solution will be either acidic or basic.

Therefore, option (b) is correct.

A chemical symbol is a shorthand method of representing an element. Instead of writing out the name of an element, we represent an element name with one or two letters.

Therefore, option (a) is correct.

The particles of rubber band are loosely bounded by force of attraction, so as we stretch it moves to maximum elastic limit and as soon as it is released it regains its shape, therefore, it has some property of solids.

The kinetic energy of particles is maximum in gas as the particles are free to roam with maximum speed as there is negligible force of attraction between the particle.

Hence the option A is correct.

A pure substance has a constant composition and cannot be separated into simpler substances by physical means. There are two types of pure substances: elements and compounds. Elements: are pure substances made up of only l type of atom. Atoms of the same element are identical in properties.

Therefore, option (a) is correct.

A pure substance that has only one kind of atom and cannot be broken into two or more simpler substances by physical or chemical means is an element.

Therefore, option (b) is correct.

The three states of matter are classified on the basis of differences of certain physical properties such as physical existence; solids are physically hard, they have fixed shape and size. Liquids do not have any fixed shape and size, they changed according to the shape of beakers in which they are placed. Gases do not have a fixed shape or volume.

An impure substance is one which is a mixture of two or more kinds of molecules and has no definite composition and properties. for example, air,soil, atones and pebbles in food grains,sugar in water,sand in water,fruit juice etc.

Therefore, option (a) is correct.