NCTB Class 7 Science Chapter 6 “Structure of Matter” Solution

Bangladesh Board Class 7 Science Solution Chapter 6 “Structure of Matter” Solution  Exercises Question and Answer by Experienced Teacher.

NCTB Solution Class 7 Chapter 6 “Structure of Matter:”

Board	NCTB Bangladesh Board
Class	7
Subject	Science
Chapter	Six
Chapter Name	“Structure of Matter”

Fill in the blanks:-

(1) Elements are made of —–component.

Ans:- Same type of.

(2) Salt and sugar are—–.

Ans:- Matters.

(3) The smallest particle of elements is called—–.

Ans:- Atom.

(4) —is the smallest particle of compounds.

Ans:- Molecule.

(5) There is—-at the centre of the atom.

Ans:- Proton.

Short answered question:-

(1)  (1) Ans:- The matters which are made of same types of components are called element. Similarly the matters which are made of more than one element are called compounds.

(1) (2) Ans:– Atom is the smallest practical of element but molecule is the smallest particle of compound. This is the main difference between atom molecule.

(1) (3) Ans:-  The main themes of Dalton’s atomic they are-

(i) Elements are made of extremely small particles called atoms.

(ii) All atoms of an element are same in size, mass and chemical properties.

(iii) Atoms of different elements differ in size, mass and other properties.

(iv)In chemical reaction, atoms cannot be created or destroyed. They just joined with and separated from, each other.

(v) Atoms of different elements combining in simple whole number ratios from compounds.

(1) (4) Ans:- By dividing atom, three particles can be found, These are- electron, proton and neutron. Neutron and proton exist in the centre of atoms and electron moves around the centre in the circular orbit.

Multiple choice questions:-

(1) The molecule of elements is—

Ans:- (c) N₂

(2) The substances of same properties showed through symbols and formula from the above table are—

Ans:- (a) 2,4

Creative question:-

(1) (a) Ans:- The symbol of Helium is he.

(1) (c) Ans:- The chemical name of number one matter are- sodium (Na) : It has 11 protons, 11 electrons and 12 neutrons.

(1) (d) Ans:- Number 2 of the table is dement because F is made of 2 same atoms which are same in size, mass and chemical reactions. In number 3, C and O .

(2) (a) Ans:- atom is the smallest partied of element.

(2) (b) Ans:- The difference between O and O₂ is the oxygen atom and O₂ is oxygen molecule.

(2) (d) Ans:- According to the diagram, the atom of a matter has 6 protons, 6 neutrons at the centre and 2 electrons outside of the atom.