Advertisements
Advertisements
Question
Define the following term of Atom .
Advertisements
Solution
Atom — An atom is the smallest part of an element that takes place in a chemical reaction.
APPEARS IN
RELATED QUESTIONS
What are molecules ?
Give one difference between atoms and molecules.
Classify the following into elements, compounds and mixtures:
- Sodium
- Soil
- Sugar solution
- Silver
- Calcium carbonate
- Tin
- Silicon
- Coal
- Air
- Soap
- Methane
- Carbon dioxide
- Blood
Describe in your own words, what happens to the particles when salt dissolves in water.
Define matter. Give four examples of matter.
During respiration, glucose and oxygen enter our body cells and waste products carbon dioxide and water leave the body cells by the process of :
The property/properties which enable copper metal to be used for making electric wires is/are :
A, B and C are all liquids. Liquid A has a comparatively low boiling point. On heating, liquid A vaporises completely without leaving behind any residue. Liquid A is being used increasingly as a fuel in motor vehicles either alone or by mixing with petrol. Liquid B has a very high boiling point. It also vaporises completely on heating, without leaving any residue. Liquid B is a conductor of electricity and used in making thermometers. Liquid C has a moderate boiling point. On heating, liquid C vaporises leaving behind a white solid D which is used in cooking vegetables. The condensation of vapours from C give a liquid E which turns anhydrous CuSO4 to blue.
(a) Which liquid could be an element ? Name this element.
(b) Which liquid could be a mixture ? Name this mixture.
(c) Which liquid could be a compound ? Name this compound.
(d) What could the solid D be ?
(e) What do you think is liquid E ?
How much water should be added to 15 grams of salt to obtain 15 per cent salt solution ?
What do you understand by the statement " the solubility of copper sulphate in water at 20°C is 20.7 g" ?
Tincture of iodine has antiseptic properties. This solution is made by dissolving :
Describe the method of separating a mixture containing common salt, sand and ammonium chloride.
Which of the following cannot be separated from air by the process of fractional distillation ?
Tincture of iodine is a mixture of two materials X and Y. The material Y has a property that its solid form can be converted directly into vapours on heating by a process called Z.
- What could X be ?
- What could Y be ?
- Name the process Z.
- Which process would you use to recover both the components X and Y from tincture of iodine ?
- Which process can be used to recover only component Y from tincture of iodine ?
Differentiate between the-two characteristics of matter – ‘mass’ & ‘weight’.
______ is not made of matter.
Name the metals that are used in jewellery.
Which among the following is not a matter?
Rusting of an article made up of iron is called
Define the term matter.
