Question

Chemistry but is a branch of science in which we

study about matter, i.e. what is matter made up of,

what is its nature, structure and what changes arecan take part in a chemical reaction.

observed when it is subjected to different conditions.

Many theories were proposed regarding matter

which helped us to discover the real essence of matter.

The basic units of matter in any state is

A set of atoms of the same type together forms

the molecule of the element. The number of atoms

in a molecule of an element is called its atomicity.

Molecules can be monoatomic, diatomic and

considered as molecules. This is because molecule

is the smallest particle of matter which has even polyatomic.
independent existence.

A pure substance is the one which is made up

of molecules containing same kind of atoms. For

example carbondioxide gas is a pure substance, all

the molecules of it are made up of two oxygen atoms

Monoatomic molecules -elements having only one

atom in their molecules. Noble gases (Helium, Neon,
Argon, Krypton, Xenon and Radon) have one atom

each in their molecules. So, the atomicity of noble

gases is one. The atomicity of metal elements like

sodium, potassium, magnesium, copper, etc. is also

taken as one. The atomicty of element carbon is also

one. Thus noble gases, metals and carbon are

and one carbon atom.

The molecule may contain similar atoms or

disimilar atoms. A pure substance in which a

molecule is made up of atoms of the same kind are

called elements.

monoatomic molecules.

Diatomic molecules - elements having two atoms

in their molecules, e.g. hydrogen (H), Oxygen (O2),

Nitrogen (N,).

An element is a simple and pure form of

matter which cannot be decomposed into simpler

Triatomic molecules - elements having three atomns

in their molecules e.g. ozone (0,).

substances.

All elements are made of atoms, the smallest

particles of an element which represent all the Tetratomic molecules- elements having f four atoms

properties of an element. in their molecules, e.g. phosphorus (P4). CAN U MAKE QUESTION OF THIS. ONLY 5​ MCQ type

Answer 1

Answer:

1.Chemistry is the branch of _______

a) science

b) maths

c) hindi

2.The number of atomsin a molecule of an element is called its__________

a) atomicity

b) molecule

c) none

3.A pure substance in which a molecule is made up of atoms of the same kind are called______

a)molecule

b) elements

c) none of the following

4.Triatomic molecules elements have how many elements?

a) one

b) two

c) 3

5. Monoatomic molecules elements have how much elements?

a) one

b) two

c) three