A molecule is in general a group of two or more atoms that are chemically bonded together, that is, tightly held together by attractive forces. A molecule can be defined as the smallest particle of an element or a compound that is capable of an independent existence and shows all the properties of that substance. Atoms of the same element or of different elements can join together to form molecules.
a molecule of oxygen consists of two atoms of oxygen and hence it is known as a diatomic molecule, O2. If 3 atoms of oxygen unite into a molecule, instead of the usual 2, we get ozone, O3. The number of atoms constituting a molecule is known as its atom.
Shaalaa.com | Atoms and Molecules (Molecules and ions)
Choose the correct answer from the options given below :
The ratio between the number of molecules in 2g of hydrogen and 32g of oxygen is :
(A) 1 : 2
(D) 0.01:1 [Given that H = 1, O = 16]
Outline the steps that would be necessary to convert insoluble lead (II) oxide into insoluble chloride.
(a) What are the terms defined by the following?
(i) A salt containing a metal ion surrounded by other ions or molecules.
(ii) A base which is soluble in water.
(b) Making use only of substances chosen from those given below:
Dilute sulphuric acidSodium Carbonate
Zinc Sodium sulphite
Lead Calcium carbonate
Give equations for the reactions by which you could obtain :
(ii) Sulphur dioxide
(iii) Carbon dioxide
(iv) Zinc carbonate (two steps required)