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AS Chemistry P2 Prep.

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wats the bond angle and shape of a compound with 2 bond pairs and 1 lone pair

2 bonds, 0 lone pair = Linear, 180 degrees, ex: CO2
2 bonds, 1 lone pair = Angular/Bent, 117 degrees, ex: SO2
2 bonds, 2 lone pair = Angular/Bent, 104.5 degrees, ex: H2O.
3 bonds, 0 lone pair = Trigonal Planar, 120 degrees, ex: AlCl3 or BF3
3 bonds, 1 lone pair = Trigonal Pyramidal, 107 degrees, ex: NH3
4 bonds, 0 lone pair = tetrahedral, 109.5 degrees, ex: CH4
5 bonds, 0 lone pair = trigonal bypyramidal, 90/120 degrees, ex: PCl5
6 bonds, 0 lone pair = Octahedral, and 90 degrees, ex: SF6.
 
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it cant be 120 cause its for trigonal planar(3 bond pairs)....... it must be 117 then b/c a lone pair
 
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They have 3 bonds each where do you see 5?

Look again. The C on the right has 2 bonds with the C on the left, 1 bond with Br, 1 with CH2Br and 1 with H. That's 5 bonds total.

The C on the left has 2 bonds with the C on the right, 1 bond with H, 1 with CH3 and 1 with the R-side chain. That's also 5 bonds total.

So each Carbon atom has 5 bonds.

There are two explanations for that; I'm missing something VERY big, OR, the Examiner had a spat with his wife the morning before making the Mark Scheme.
 
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Look again. The C on the right has 2 bonds with the C on the left, 1 bond with Br, 1 with CH2Br and 1 with H. That's 5 bonds total.

The C on the left has 2 bonds with the C on the right, 1 bond with H, 1 with CH3 and 1 with the R-side chain. That's also 5 bonds total.

So each Carbon atom has 5 bonds.

There are two explanations for that; I'm missing something VERY big, OR, the Examiner had a spat with his wife the morning before making the Mark Scheme.
Its mis printing for double bond
 
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ok have 1 doubt..
all grpI MNO3 decompose to MNO2 + O2
but Li haas high polarising power so it decompose like grpII M(NO3)2............... LNO3 ---->MO2 +NO2 or MO2 +NO2 +O2 as well...?
do Li on decomposition releases O2 or not ? dats my doubt...
 
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Jazak Allah Khayr.

Can someone please explain to me the reactions of KMnO4 on Alkenes?
If the end of the molecule contains CH2 then CH2 is converted into H20 and CO2. The other side of the molecule must contain 2 bond, i.e CH and an other R group. The CH molecule is always converted into COOH. For eg, CH3-CH=CH2 = CH3COOH+CO2+H20.
Furhtermore there is a possibltiy that the left side of the molecule contains 2 R gps other than CH, if this happens then the resulting molecule is R-C-R with a double bond ketone oxygen group above oxygen. For e.g (CH3)2=CH2 = CH3_C(=O)-CH3+ Co2 + H2O
 
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Jazak Allah Khayr.

Can someone please explain to me the reactions of KMnO4 on Alkenes?

Also, why does only KMnO4 show that kind of reaction with Alkenes; why doesn't K2Cr2O7, as they're both oxidizing agents?
Regarding K2Cr2O7 this is a weak oxidising agent where Kmno4 is a strong oxidising agents so K2cr2O7 is only able to oxidise to OH, where Kmno4 furhter oxidises to ketone or CooH
 
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