The percentage of oxygen in $NaOH$ is
- 0.16
- 0.04
- 0.4
- 0.08
The Correct Option is C
Approach Solution - 1
Approach Solution -2
Ans: For the percentage of oxygen in NaOH, we can calculate the mass fraction of oxygen in the compound.
The chemical formula of sodium hydroxide is NaOH. It means the atoms that are present in this compound are 1 sodium, 1 oxygen and 1 hydrogen.
The molar mass of all these atoms present in the compounds are as follows:
Molar mass of Na= 22.99 g/mol
Molar mass of O= 16 g/mol
Molar mass of H= 1 g/mol
Therefore, the molar mass of the compound will be NaOH= 22.99+16+1 = 40 g/mol
The mass fraction of oxygen = mass of oxygen /molar mass of NaOH x100
= 16/40 X100
That is approximately 40%
Therefore, the answer is 40%
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Concepts Used:
Some Basic Concepts of Chemistry
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.