Chemistry

PF₅, PCl₅, PBr₅, Fe (CO)₅ Þ Trigonal bipyramidal

BrF₅ Þ Square pyramidal

[PtCl₄]^2– Þ Square planar

SF₆ Þ Octahedral

Boiling point: $\stackrel{\left(239.7\right)}{N{H}_3}>\stackrel{\left(185.5\right)}{P{H}_3}$  due to hydrogen bonding in NH₃.

Order of reactivity towards electrophile

Strength of +M/+R : –OH > –CH₃ > –Cl

In case of halogens, their –I effect dominates over

+M hence –Cl is deactivating and  is lesser reactive than  for incoming electrophile.

CuSO₄ acts as catalyst in Kjeldahl's method of estimation of nitrogen.

This is an example of chromyl chloride test

K₂Cr₂O₇ + 4KCl + 6H₂SO₄? 6KHSO₄ + 2CrO₂Cl₂ + 3H₂O

Oxidation state of Cr is +6.

The balanced reaction is as follows

$2Mn{O}_4^{-}+5C_2{O}_4^{2+}+16H^{+}\to 2M{n}^{2+}+10C{O}_2+8H_{2}O$            

2 mole  $Mn{O}_4^{-}$ react with 16 mole H⁺

1 mole  $Mn{O}_4^{-}$ will react with 8 mole H⁺

A, D, E, K vitamins are fat soluble vitamins, are stored in liver and adipose tissue.

While vitamin B and vitamin C are water soluble and must be supplied regularly in diet (not stored) (except vitamin B₁₂)  

$w=-nRTln\frac{V_2}{V_1}$

$\left|w\right|=2.303nRTlog\frac{V_2}{V_1}$

$\left|w\right|=1*2.303*8.314*300log\frac{100}{10}$        

|w| = 5744 J

|w| = 5.744 kJ » 6 kJ

$t_{90}=\frac{2.303}{k}log\left(\frac{100}{100-90}\right)$

$=\frac{2.303*36}{2.303*log2}*log10=\frac{36}{0.3}=120$