New Concepts/Shortcuts 19

Question 1

the formula for new means if the wrong observation is deleted and the new one is added

Answer 1

Question 2

why does the stability of peroxide or superoxide increase as the size of the metal increases?

Answer 2

due to the stabilization of large anions by larger cations through lattice energy

Question 3

metals with liquid ammonia forms? and then on concentration forms?

Answer 3

Question 4

what trend Does the MP and BP of halogens always follow?!

Answer 4

Question 5

the low solubility of LiF in water is due to the?

Answer 5

its higher lattice enthalpy

Question 6

the low solubility of CsI is due to?

Answer 6

smaller hydration enthalpy

Question 7

LiCl and MgCl2 are soluble in?

Answer 7

ethanol

Question 8

hydrogen carbonates are not formed by which metals?

Answer 8

Li and Mg

Question 9

why cant the potassium carbonate be produced from the Solvay process?

Answer 9

because potassium hydrogen carbonate is too soluble in the ammonium hydrogen carbonate

Question 10

which grp 2 element is not alkaline earth metal?

Answer 10

beryllium

Question 11

hydration enthalpy of alkaline earth metals is more/less than the hydration enthalpy of alkali metals?

Answer 11

hydration enthalpy of alkaline earth metals is more than the hydration enthalpy of alkali metals?

Question 12

most reducing earth metal is?

Answer 12

barium

Question 13

which alkaline earth metals do not give flame test

Answer 13

beryllium and magnesium

Question 14

beryllium in which form reacts with air and what does it form?

Answer 14

Be in powdered form reacts with air and burns brilliantly on ignition in the air to give BeO and Be3N2

Question 15

which alkaline metal does not combine with Hydrogen upon heating to form its hydride?

Answer 15

Beryllium

Question 16

how can BeH2 be created?

Answer 16

Question 17

why are metal fluorides less soluble than chloride?

Answer 17

high lattice energies

Question 18

the tendency to form halides generally increases or decreases down the grp for alkaline earth metals?

Answer 18

decreases down the grp

Question 19

chlorides of which metals have a Cli bridge in vapor phase?

Answer 19

Be and Al

Question 20

just keep this in mind

Answer 20

Question 21

important ingredients present in Portland cement are?

Answer 21

tricalcium silicate (3CaO · SiO2)
dicalcium silicate (2CaO · SiO2)
tricalcium aluminate (3CaO · Al2O3)
tetra-calcium aluminoferrite (4CaO · Al2O3Fe2O3).

Question 22

whats glyptal? what is it made up of and where is it used?

Answer 22

it is used in paints and lacquer

Question 23

dacron made of?

Answer 23

ethylene glycol and terephthalic acid

Question 24

nylons/polyamide is an eg of which kind of polymers?

Answer 24

condensation polymers

Question 25

novolac formation reaction

Answer 25

Question 26

bakelite structure

Answer 26

Question 27

melamine formation reaction

Answer 27

Question 28

how is PHBV formed and what's the full form of PHBV?

Answer 28

poly beta-hydroxybutyrate - co-beta-hydroxy valerate

Question 29

eg of biodegradable polymers?

Answer 29

PHBV | nylon 2-nylon 6

Question 30

K2MnO4 in acid forms!?

Answer 30

Question 31

eg of fat-soluble vitamins and eg of water-soluble vitamins

Answer 31

fat soluble:- A,D,E,K water soluble:- B grp and C

Question 32

eg of fat-soluble vitamins and eg of water-soluble vitamins

Answer 32

fat soluble:- A,D,E,K water soluble:- B grp and C

Question 33

vitamins that should be supplied regularly in diest are? and why?

Answer 33

water-soluble vitamins( B grp and C) because they are readily excreted in urine and cannot be stored in our body

Question 34

which water soluble vitamins can not be readily excreted in urine and cannot be stored in our body

Answer 34

B 12

Question 35

Answer 35

Question 36

length of antenna formula

Answer 36

lambda being the wavelength of the signal

Question 37

energy density formula for electric and magnetic field

Answer 37

Question 38

partially filled dileectric formula

Answer 38

Question 39

what are polycrystalline solids?

Answer 39

there are some solids that apparently appear amorphous but have microcrystalline structures these are polycrystalline solids metals often occur in polycrystalline condition

Question 40

Answer 40