P Block 1

Question 1

Grp 13 radii

Answer 1

Question 2

Grp 13 IE

Answer 2

Question 3

Grp 13 MP

Answer 3

Question 4

Grp 13 density order

Answer 4

increases from B to Tl

Question 5

Tendency to behave like an Lewis acid for halides decreases / increases down the grp?

Answer 5

decreases

Question 6

Color of boron

Answer 6

hard black colored solid

Question 7

Why is gallium useful for measuring high temperatures?

Answer 7

gallium has an unusually low melting point and hence exists in a liquid state during summer!

Question 8

Trichlorides on hydrolysis in water form what?

Answer 8

tetra hedral [M (OH)4]-

Question 9

Which type of boron reacts with stuff

Answer 9

amorphous boron reacts

Question 10

TlI3 structure(thallium)

Answer 10

its made of Ti3+ and I-3

Question 11

White fumes appear from the bottle of AlCl3, why!?

Answer 11

anhydrous aluminum chloride is partially hydrolyzed with the atmospheric moisture to liberate HCl gas, Moist HCl appears white in color

Question 12

Boron structure draw B12(and how many corners and faces)

Answer 12

Question 13

Extraction of boron(From colemanite)

Answer 13

Question 14

Borax formula both type

Answer 14

Question 15

Borax beads forming process

Answer 15

Question 16

Borax bead color of different metals(Fe,Co,Cu,Ni,Cr)

Answer 16

Question 17

Orthoboric acid formula and struture

Answer 17

H3BO3

Question 18

Orthoboric acid in water forms

Answer 18

Question 19

Orthoboric acid heated

Answer 19

Question 20

What is added in titration reaction to get end point with H3Bo3 as acid

Answer 20

cis 1,2 diolnis is added

Question 21

Diborane prep from LiAlH4 and__ and the whole reaction

Answer 21

Question 22

Diborane color, toxicity

Answer 22

colorles and highly roxic

Question 23

Diborane number of 3c 2e and 2c 2e bonds plus structure

Answer 23

2 3c 2e bonds4 2c 2e bonds

Question 24

Diborane with exposure to air reaction

and is it spontaneous or not and what abt its explosivity

Answer 24

yes spontaneous and explosive

Question 25

Diborane with ammonia forms and then when heated the product..!?

Answer 25

Question 26

What is used in making bullet proof vests

Answer 26

boron fibres are used 

Question 27

Boron is used as what in the nuclear industry

Answer 27

control rods as it can absorb the neutrons 

Question 28

Which isotope of boron can absorb neutrons

Answer 28

Boron-10

Question 29

Which isotope of carbon is radioactive

Answer 29

C-14

Question 30

aluminum chloride in acidified aqueous solution forms ____ 

Answer 30

octahedral [Al (H2O)6]3+ 

Question 31

Borax structure

Answer 31

Question 32

what sthe angle between B-H-B bond in diborane

Answer 32

90 degree

Question 33

which boron halide can behave as lewis acid when reacting with its ionic form

Answer 33

Question 34

Answer 34

Question 35

Answer 35

Question 36

Answer 36

Question 37

Answer 37

AlOH3 is white ppt and formed whaen NaOH is in limit in excess it forms the below product

Question 38

LiH with B2H6 forms?

Answer 38

Question 39

Answer 39

all boron atoms are not in the same plane as 2 atoms are sp2 hybridised and 2 are sp3 hybridised the B with 4 bonds is sp3

Question 40

Answer 40

it behaves as a weak acid due to releasing H+ and and forming B(OH)4^1- adding ethylene glycol results in the reaction between it and the B(OH)4^1- which hence leads to protection of the latter in getting into the reverse reactions and hence it will become more and more acidic due to the releasing of H+ ions

Question 41

Answer 41

Al(CH3)3 has 2e electrons from the bond of Al-C and 3 centers (Al-C-Al) hence it's a 2e 3c bond AlCl3 dimer has 2 electrons from the Cl atom and 2 e from the Al-C electrons and 3 centers (Al-C-Al) and hence 4e 3c bond BCl3 doesn't form a dimer and hence has the deficiency which makes it a good lewis acid whereas AlCl3 forms a dimer and hence the deficiency isn't there which makes it a bad lweis acid

Question 42

Answer 42

the lone pair on N gets distributed to the vacant orbitals of Si and hence it's not planar also the electrons are not much available for the donation which makes it less basic

Question 43

why does B have the highest melting point?

Answer 43

because it has a 3D structure

Question 44

back bonding strength order of boron halides

Answer 44

Question 45

mohr's salt and potash alum formulae

Answer 45