The Periodic Table

Question 1

Examples of noble gases

Answer 1

Helium,neon,argon,krypton,xenon,radon

Question 2

Uses of helium

Answer 2

Used in ballons and airship

Question 3

Uses of argon

Answer 3

Filling light bulb

Question 4

Use of neon

Answer 4

Lamps and advertisment signs

Question 5

Why they replaced hydrogen with helium?

Answer 5

Because hydrogen is flammable but helium is not

Question 6

Why argon used in filling light bulbs?

Answer 6

Because it is an inert atmosphere that doesn’t lose or gain electrons easily and to protect the filament from burning

Question 7

What is phisical properties of alkali metals?

Answer 7

-they have shiny silver surface
-They are soft
-they have low densities
-they have low melting point
They are good conductor of electricity and heat

Question 8

What is melting point of lithium

Answer 8

180

Question 9

What is melting point of potassium

Answer 9

64

Question 10

Why lithium float on water?

Answer 10

Because they are less dense than water

Question 11

Periodic table is obtained by arranging elements in order of_______

Answer 11

Increase atomic number

Question 12

How many elements in group and how many found in nature

Answer 12

116
92 found in nature

Question 13

How many periods and groups in periodic table

Answer 13

7 periods
8 main group

Question 14

All elements in same period have _______

Answer 14

Same number of energy shells

Question 15

Why number of electrons in the valence shell increases by one?

Answer 15

Because atomic number increase by one which leads to periodicity in chemical properties across the period

Question 16

Why elements in the same group have same chemical properties

Answer 16

Because they have same number of electrons in the valence shell which is equal to group’s number

Question 17

What is a period’s number

Answer 17

Number of shells filled with electrons

Question 18

What is group’s number

Answer 18

Number of electrons in the outermost shell

Question 19

Examples of gas element

Answer 19

Hydrogen, nitrogen, oxygen, fluorine, chlorine, noble gases

Question 20

Example of liquid metal

Answer 20

Mercury

Question 21

Example of liquid non metal

Answer 21

Bromine

Question 22

Why atoms of all elements tend to combine with each other

Answer 22

In order to get the electronic structure of the nearest Noble gas

Question 23

Why Carbon and silicon don’t form ions?

Answer 23

As the maximum number of electrons that can be lost or gained is only three electrons

Question 24

Why hydrogen is difficult to place it in periodic table?

Answer 24

Because it is smallest atom of all it’s properties are distinctive,unique and doesn’t fit easily