PERIODic table

Question 1

give the formula of sodium sulfide

Answer 1

na2s

Question 2

explain in terms of electronic configuration why neon is unreactive

Answer 2

it doesnt lose or gain or share electrons,because its outermost shell is full

Question 3

how are elements arranged in the periodic table

Answer 3

increasing atomic number

Question 4

why argon is least reactive element

Answer 4

doesnt lose or gain electrons or shared electron

Question 5

symbol of silver

Answer 5

ag

Question 6

state a phisical proprety shows na is metal

Answer 6

as its good conductor of electricity

Question 7

suggest why argon is a more suitable gas that air to use in light bulb

Answer 7

as argon provide an inert atmosphere to protect the filement from burning as argon cant lose gain or shared electrons

Question 8

name 2 ellements in period 2 that form acidc oxide

Answer 8

carbon,nitrogen

Question 9

How many elements in periodic table

Answer 9

116 element

Question 10

How many periods and group in periodic table

Answer 10

7 period
8 group

Question 11

Same period means same number of_____

Answer 11

Energy level

Question 12

Why numbering electrons in same period have same number of energy level?

Answer 12

As number increase by one which lead to periodicity in chemical properties across period

Question 13

Why elements in same group have same chemical properties?

Answer 13

As same number of electrons in valence shell equal group’s number

Question 14

Why hydrogen not place in periodic table?

Answer 14

As it’s smallest atom,unique, not fit easily,properties is distinctive

Question 15

What’s meant by period’s number

Answer 15

Number of shells filled with electrons

Question 16

What is meant by a group’s number

Answer 16

Number of electrons in outermost shell

Question 17

Example of gas elements

Answer 17

Hydrogen,nitrogen,oxygen fulorine, chlorine,noble gas

Question 18

Example of liquid element (metal)

Answer 18

Mercury

Question 19

Example of liquid non-metal

Answer 19

Bromine

Question 20

Why atoms of all elements tend to combine with each other?

Answer 20

In order to get electronic structure nearest noble gas

Question 21

Metal react with non-metal gives____

Answer 21

Ionic compound

Question 22

Non-metal react with non-metal gives____

Answer 22

Covalent compound

Question 23

What is meant by valence shell

Answer 23

Number of electrons can be lost,gained,shared to attain stable electronic structure

Question 24

Why reactivity of metals increase down group?

Answer 24

As valence electron get further from nucleus

Question 25

Metal form _____

Answer 25

Basic oxide

Question 26

Non-metal form____

Answer 26

Acidic oxide

Question 27

What us the valency number of zn

Answer 27

2

Question 28

What is the valency number of lead

Answer 28

2

Question 29

What is valency number of iron

Answer 29

2 or 3

Question 30

What is the valency number of copper

Answer 30

1 or 2

Question 31

Examples of inert gasess

Answer 31

Helium,neon,argon,krypton,xenon ,radon

Question 32

Uses of helium

Answer 32

Filling ballon and airships

Question 33

Uses of argon

Answer 33

Fill light bullb

Question 34

Usage if neon

Answer 34

Lamps and advertisment lamp

Question 35

Why we use heliumin filling balloon and airships

Answer 35

As it’s very light and less dense than air and doesn’t burn

Question 36

What is group vii

Answer 36

Halogen

Question 37

How many electron outer shell of non-metal

Answer 37

4 electrons or more

Question 38

Say some general propreties of translation metal

Answer 38

Form coloured compound
Transation metals compounds used as catalyst
More than one valency
Higher denisty and Higher m.p and b.pexcept hg

Question 39

Some general properties of metals

Answer 39

Outer most shell incomplete is less than 4
Lose electron and form positive ion
Metal form basic oxide
Group 1 is alkali metals
Group 2 is earth alkali metals
Good conductor of heat and electricity, ductile,mallible