Complete guide to "Is Matter Around Us Pure" for Chemistry students. Below you will find important questions and model answers to help you prepare.
We are building a dedicated quiz for this topic, but you can test your skills on a similar concept: The Fundamental Unit of Life - NCERT Class 9 Practice Set 1.
Which of the following statements are true for pure substances? (i) Pure substances contain only one kind of particles (ii) Pure substances may be compounds or mixtures (iii) Pure substances have the same composition throughout (iv) Pure substances can be exemplified by all elements other than nickel
(i) and (ii)
(i) and (iii)
(iii) and (iv)
(ii) and (iii)
Rusting of an article made up of iron is called
corrosion and it is a physical as well as chemical change
dissolution and it is a physical change
corrosion and it is a chemical change
dissolution and it is a chemical change
A mixture of sulphur and carbon disulphide is
heterogeneous and shows Tyndall effect
homogeneous and shows Tyndall effect
heterogeneous and does not show Tyndall effect
homogeneous and does not show Tyndall effect
Tincture of iodine has antiseptic properties. This solution is made by dissolving
iodine in potassium iodide
iodine in vaseline
iodine in water
iodine in alcohol
Which of the following are homogeneous in nature? (i) ice (ii) wood (iii) soil (iv) air
(i) and (iii)
(ii) and (iv)
(i) and (iv)
(iii) and (iv)
Which of the following are physical changes? (i) Melting of iron metal (ii) Rusting of iron (iii) Bending of an iron rod (iv) Drawing a wire of iron metal
(i), (ii) and (iii)
(i), (ii) and (iv)
(i), (iii) and (iv)
(ii), (iii) and (iv)
Which of the following are chemical changes? (i) Decaying of wood (ii) Burning of wood (iii) Sawing of wood (iv) Hammering of a nail into a piece of wood
(i) and (ii)
(ii) and (iii)
(iii) and (iv)
(i) and (iv)
Two substances, A and B were made to react to form a third substance A₂B, according to the following reaction. 2A + B → A₂B Which of the following statements concerning this reaction are incorrect? (i) The product A₂B shows the properties of substances A and B (ii) The product will always have a fixed composition (iii) The product so formed cannot be classified as a compound (iv) The product so formed is an element
(i), (ii) and (iii)
(ii), (iii) and (iv)
(i), (iii) and (iv)
(ii), (iii) and (iv)
Two chemical species X and Y combine together to form a product P which contains both X and Y X + Y → P X and Y cannot be broken down into simpler substances by simple chemical reactions. Which of the following concerning the species X, Y and P are correct? (i) P is a compound (ii) X and Y are compounds (iii) X and Y are elements (iv) P has a fixed composition
(i), (ii) and (iii)
(i), (ii) and (iv)
(ii), (iii) and (iv)
(i), (iii) and (iv)