Advertisements
Advertisements
Question
Which of the following statements are true for pure substances ?
- pure substances contain only one kind of particles
- pure substances may be compounds or mixtures
- pure substances have the same composition throughout
- pure substances can be exemplified by all elements other than nickel
Options
(i) and (ii)
(i) and (iii)
(iii) and (iv)
(ii) and (iii)
Advertisements
Solution
(i) and (iii)
A pure substance is made up of only one kind of particles like elements. The composition of pure compounds is also same throughout.
APPEARS IN
RELATED QUESTIONS
Liquids have definite shape and definite volume.
What is the scientific name of particles which make up mater?
The best evidence for the existence and movement of particles in liquids was provided by :
Fill in the following blanks with suitable words :
The elements which are sonorous are called ..........................
Explain why, hydrogen and oxygen are considered elements whereas water is not considered an element.
The elements which normally exist in the liquid state are :
In the following set of substances, one item does not belong to the set. Select this item and explain why it does not belong to the set :
Hydrogen, Oxygen, Steam, Chlorine
What is the most common way of expressing the concentration of a solution ?
Choose one term from the following which includes the other three :
aerosol, emulsion, colloid, sol
Explain what happens when a beam of light is passed through a colloidal solution.
Differentiate between a saturated and an unsaturated solution. How will you test whether a given solution is saturated or not ?
Which of the following represents the solubility of sugar in water at 20°C ?
Which one of the following is not a chemical change ?
The solubility of ammonium chloride in water at various temperatures is given below :
| Temperature | : | 10°C | 20°C | 40°C | 60°C | 80°C |
| Solubility | : | 24 g | 37 g | 41 g | 55 g | 66 g |
What mass of ammonium chloride would be needed to make a saturated solution of ammonium chloride in fifty grams of water at 40°C ?
How is water purified on a large scale at water works ? Explain with the help of a labelled diagram. Name the substance which is added to kill germs in the drinking water supply ?
What is fractional distillation ? What is the use of fractionating column in fractional distillation ?
One of the following does not undergo sublimation. This one is :
Justify your answer.
| Figure 1 | Figure 2 | Figure 3 |
![]() |
![]() |
![]() |
The arrangement of particles in three different phases of matter is shown above.
- Which state is represented by Fig. 1?
- In which state will the inter-particle attraction be maximum?
- Which one of them cannot be contained in an open vessel?
- Which one can take the shape of its container?
Give some examples of the Tyndall effect observed in your surroundings?
Evaporation is always accompanied by ______ in temperature.



