Convert the following into basic units:- 28.7 pm
- 15.15 pm
- 25365 mg
- 28.7 pm
- 15.15 pm
- 25365 mg
Solution and Explanation
(i) 28.7 pm:
1 pm = 10-12 m
∴ 28.7 pm = 28.7 × 10-12 m
= 2.87 × 10-11 m
(ii) 15.15 pm:
1 pm = 10-12 m
∴ 15.15 pm = 15.15 × 10-12 m
= 1.515 × 10-11 m
(iii) 25365 mg:
1 mg = 10-3 g
25365 mg = 2.5365 × 104 × 10-3 g
Since,
1 g = 10-3 kg
2.5365 × 101 g = 2.5365 × 101 × 10-3 kg
∴ 25365 mg = 2.5365 × 10-2 kg
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Concepts Used:
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Chemistry is a vast subject and for understanding its significance we can take help of following points:
- Chemistry plays an important role in understanding various subjects like physics, geology and biology.
- Chemistry is a core branch of science that explains us about the various compositional properties and interaction of matter. It also helps to understand various chemical reactions.
- Chemistry is important in order to understand the behaviour of fertilizers, alkenes, acids, salts, dyes, polymers, drugs, soaps and alloys in organic and inorganic chemistry.
- Chemistry plays an important role in various fields like healthcare, industrial, research, food, and farm activities.
Read More: Some Basic Concepts of Chemistry
Classification of Matter
There are two ways of classifying the matter:
(A) Physical Classification:
Matter can exist in three physical states:
- Solids - have definite volume and definite shape
- Liquids - have definite volume but not definite shape.
- Gases - have neither definite volume nor definite shape.
(B) Chemical Classification:
Based upon the composition, matter can be divided into two main types:
- Pure Substances are defined as a single substance (or matter) which cannot be separated by simple physical methods. Pure substances can be further classified as (i) Elements (ii) Compounds
- Mixtures are the combination of two or more elements or compounds which are not chemically combined together and may also be present in any proportion.