p block (o family)

Question 1

oxygen family

Answer 1

oxygen
sulphur
selenium
telurium
polonium
livermorium

Question 2

livermorium

Answer 2

extremely radioactive and synthetic,unseen

Question 3

mettallic char

Answer 3

oxygen,sulphur are non metals
selenium and tellurium are metalloids
polonium metallic also radioactive with a very short half life

Question 4

most abundant element

Answer 4

oxygen

Question 5

role of oxygen in the weigth of earths crust and water in oxygen

Answer 5

earths crust-silicate minerals-46.6%
ocean water-89%

Question 6

16th most abundant in earths crust

Answer 6

sulphur

Question 7

sulphur occur as sulphates such as

Answer 7

gypsom CaSO4.2H2O
epsom salt MgSO4.7H2O
baryte BaSO4

Question 8

sulphur occur as sulphides such as

Answer 8

galena
zinc blende
sopper pyrates

Question 9

principle source of Se,
Te

Answer 9

anode mud deposited during the refining of Cu

Question 10

decay prdt of thorium and uranium

Answer 10

polonium

Question 11

ec

Answer 11

ns2 np4

Question 12

IE

Answer 12

IE1 is lower than corresponding 15
IE2 is higher than corresponding 15
[ due to symmentrical and more stable ec of grp 15 ]

Question 13

why electron gain enthalpy of oxygen is the least negative

Answer 13

bcos of its small size,electron electron replusion in the relatively 2p orbtal are high hence the incoming electrons are not accepted

Question 14

most en element

Answer 14

oxygen

Question 15

why grp 16 is less metallic

Answer 15

high ionisation enthalpy

Question 16

insulater

Answer 16

sulphur

Question 17

semiconductors

Answer 17

selinium and telurium [metalloids]

Question 18

melting point and boiling point

Answer 18

increases doent the grp
as size increases
wan der vaals force of attraction increases

Question 19

elemental state

Answer 19

oxygen is diatomic others are octaatomic

Question 20

catenation

Answer 20

sulphar has more interest than oxygen becaus single bons btw sulphur is more stronger

Question 21

allotropy

Answer 21

oxygen-dioxygen,ozone or trioxygen
sulphur has several allotropic forms

Question 22

how conduction and intensity of light realted

Answer 22

as intensity of light increases
conduction increases

Question 23

…… used for measuring the intensity of light

Answer 23

selenium

Question 24

formation of hydride

Answer 24

H2E

Question 25

bond angle btw hydrides

Answer 25

decreases down the grp

Question 26

volatility order

Answer 26

h2s>h2se>h2te>h2o
size increases wan der waals force increases
h2o has interatomic h bonding

Question 27

reactivity towards oxygen

Answer 27

EO2,EO3

Question 28

ozone and SO2 are……… at room temp

Answer 28

gases

Question 29

SeO2,TeO2,PoO2

Answer 29

crystalline ionic solids

Question 30

trioxides of grp 16

Answer 30

acidic in nature
in the form EO3.O3
SO3 are gases