MD SR. SEC SCHOOL, MANKROLA

CLASS – 8TH

SUBJECT- SCIENCE DATE : 23/7/2020

Good morning dear students.

I Hope you are safe and healthy at your home.

Students In today’s topic we will study about the Different physical properties of metals and non

metals.

Do these notes in your fair note book.

Students Your work should be Neat and clean.

CHAPTER – 4 METALS AND NON- METALS

Introduction -

Everything around us is categorized into either metals or non-metals. Hence, it is important to know what non-metals and metals are and how to distinguish them. The class 8 science chapter 4 discusses the various physical and chemical properties of metals and non-metals. To help you with it, here we list a few physical and chemical properties of metals and non-metals.

Metals :

Metals are described as chemical elements that readily lose valence electrons to form positive ions (cations). Examples: Aluminium, copper, iron, tin, gold.

Around 90 of the total 118 elements are metals.

Physical Properties :

Physical Properties of Nonmetals -

Occur as solids, liquids, and gases at room temperature

Brittle

Non-malleable

Non-ductile

Non-sonorous

Bad conductors of heat and electricity

Exceptions in Physical Properties:

Alkali metals (Na, K, Li) can be cut using a knife.

Mercury is a liquid metal.

Lead and mercury are poor conductors of heat.

Mercury expands significantly for the slightest change in temperature.

Gallium and cesium have a very low melting point

Iodine is non-metal but it has lustre.

Graphite conducts electricity.

Diamond conducts heat and has a very high melting point.

Physical Properties of Metals :

● Hard and have a high tensile strength ● Solids at room temperature, except mercury, which is liquid at room temperature. ● Sonorous ● Good conductors of heat and electricity ● Malleable, i.e., can be beaten into thin sheets ● Ductile, i.e., can be drawn into thin wires ● High melting and boiling points (except Cesium (Cs) and Gallium (Ga)) ● Dense, (except alkali metals). Osmium – highest density and lithium – least density ● Lustrous ● Silver-grey in colour, (except gold and copper)

Non-Metals:

Non-metals are those elements, which do not exhibit the properties of metals. Examples: Carbon, Boron etc.

M.D. SENIOR SECONDRY SCHOOL-MANKROLA(GRG)

HOMEWORK FILE

CLASS-VIII

SUBJECT-ENGLISH

DATED-23-07-20

1. ENGLISH GRAMMAR- LEARN CHAPTER-3

AUXILIARIES AND MODALS

2. FILL THE BLANKS RELATED TO THIS CHAPTER AND WRITE

THEM IN YOUR COPY.

SECTION –A

SECTION-B

ANSWER-SECTION-A

OUGHT TO, MUST, SHOULD, SHALL, MIGHT, USED, WOULD,

SHOULD, WILL, COULD, WOULD, WOULD, WILL ,NEED TO,

OUGHT TO, SHOULD, WOULD, CAN, MIGHT,MAY,

ANSWER-SECTION-B

CAN, SHALL, CAN, WOULD, WILL, DID, CAN, SHOULD, WOULD,

DO, SHOULD, COULD, CAN, WILL, CAN.

Class:-8th Date:- 23 July, 2020

Subject:- Computer Home work

Read Ch:-3 Creating Web Page in HTML

Page no. 33

HOME ASSIGNMENT OF 8th

CLASS MATHS DATE: 23.07.2020 CHAPTER -3 [SQUARES AND SQUARE ROOTS ] ASSIGNMENT - 3.1

Do the following in your fair notebook .

SOLUTION OF THESE QUESTIONS :-