P BLOCK (2) 17 and 18 Flashcards

1
Q

% of iodine in seaweeds

A

0.5%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

chile salt petre contains

A

0.2% of sodium iodate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

atomic and ionic radii in group 17

A

increases down the group

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

order of IE in group 17

A

decreases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

order of Electron gain enthalpy

A

F<Cl>Br>I</Cl>

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Order of EN

A

F>Cl>Br>I

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

order of MP and BP

A

increases steadily

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

why are all halogens colored?

A

This is due to the absorption of radiation visible region which results in the excitation of outer electrons to a higher energy level. By absorbing different quanta of radiation, they display different colors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

fluorine and chlorine are soluble in

A

water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Bromine and iodine are soluble in

A

organic solvents: they are sparingly soluble in water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Although the electron gain enthalpy of fluorine is less negative as compared to chlorine, fluorine is a stronger oxidizing agent than chlorine. Why?

A

low enthalpy of dissociation of F-F bond and high hydration enthalpy of F–

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

oxidation states exhibited by chlorine, bromine, and iodine?

A

+1, +3, +5, +7

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

higher oxidation states of chlorine, bromine, and iodine are realized when?

A

In combination with the small and highly
electronegative fluorine and oxygen atoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

when does chlorine and bromine exhibit +4 and +6

A

with oxides and oxoacids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

fluorine exhibits only

A

-1 state

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

which is the strongest oxidizing agent among halogens

A

fluorine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

fluorine reacts with water to form

A

oxygen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Chlorine and Bromine react with water to form

A

hydrohalic and hypohalous

19
Q

most of the reactions of fluorine are

A

exothermic

20
Q

oxides of fluorine

A

OF2 and O2F2

21
Q

thermally stable oxide of fluorine

A

OF2

22
Q

O2F2 oxidises plutonium to

A

PuF6

23
Q

the order of stability of oxides of halogens

A

I>Cl>Br

24
Q

what is the reason for the higher stability of oxides of iodine?

A

due to the greater polarising character of I-O bond

25
Q

why are oxides of chlorine more stable than the oxides of Bromine?

A

because chlorine can form multiple bonds with oxygen due to the availability of d orbitals

26
Q

which is the oxide of chlorine that is used as a bleaching agent in the paper pulp and textiles industry, and in water treatment.

A

ClO2

27
Q

Bromine oxides exist only at

A

low temperatures

28
Q

which is the oxide used in CO estimation?

A

I2O5

29
Q

The ionic character of metal halides is in the order?

A

MF>MCl>MBr>MI

30
Q

group 18 is called noble gases because

A

they form very few compounds

31
Q

Helium and sometimes neon are found in
minerals of radioactive origin e.g.,

A

pitchblende, monazite, cleveite

32
Q

what is the main commercial source of He?

A

natural gas

33
Q

the abundance of noble gases in the atmosphere?

A

1%

34
Q

which are the gases not found in the atmosphere?

A

radon and oganesson

35
Q

electron gain enthalpy is

A

large and positive

36
Q

solubility of noble gases

A

sparingly soluble

37
Q

why is their boiling point very low?

A

because they only have weak dispersion forces between them

38
Q

Which noble gas has the lowest boiling points

A

He with 4.2 K

39
Q

the red compound of Xe was first synthesized by

A

Neil Bartlett

40
Q

the compound of Kr that is studied in detail?

A

KrF2

41
Q

XeO3 is a

A

colorless, explosive solid

42
Q

XeOF4 is a

A

colorless, volatile liquid

43
Q

XeO3 is formed by the hydrolysis of?

A

XeF4 and XeF6

44
Q

products of partial hydrolysis of XeF6

A

XeOF4 and XeOF22