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No hydrogen bond is formed only when hydrogen is directly bonded to fluorine, nitrogen or oxygen.
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Chemistry: Post your doubts here!
- Thread starter XPFMember
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yeh the requirements for a hydrogen bond are:
1. H atom attached to a highly electronegative atom
2. an unshared pair of electrons on the electronegative atom.
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Umm... dude you're negating yourself.Yea thats permanent dipole dipole interaction but what i meant was that Van der Waal's forces comprise of 2 types of forces. One is dipole dipole interactions and the other is dispersion forces(aka temporary induced dipoles or London forces)
As far as I know Instantaneous dipole-Induced dipole (temporary dipoles) forces have London Forces and Van der Waal's forces under them.
And then dipole-dipole forces are basically permanently dipole-permanently dipole forces... the one between two polar molecules.
You have to mug up some angles like ammonia 109.5 tetrahydral, water 104.5, Bf3 120 triagular . These are similar then to find out the bond angels compare with these and youll find out. Just compare the lone pairs of with them which ever matches bond angle is that.
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no no ure getting confused. All intermolecular forces are collectively known as Van der Waal's forces. The various different types were first explained by different people at different times. Dispersion forces that are temporary and induced dipoles were first introduced by London in i think 1930 hence temproary and induced dipoles are also known as London Forces. Dipole Dipole interactions were first explained by Keesom in 1912. But the bottom line is that all of them are collectively referred to as Van der Waals forces!
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Thank you guys for the help, I understood some stuff that I've had trouble with all year. It's funny how you start understanding things better when the exam is nearby.
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Sorry not ALL intermolecular forces are Van der Waals. Hydrogen Bond is not included in Van der Waals forces.
Excuse my poor painting skills. Hope you got the point.
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no no ure getting confused. All intermolecular forces are collectively known as Van der Waal's forces. The various different types were first explained by different people at different times. Dispersion forces that are temporary and induced dipoles were first introduced by London in i think 1930 hence temproary and induced dipoles are also known as London Forces. Dipole Dipole interactions were first explained by Keesom in 1912. But the bottom line is that all of them are collectively referred to as Van der Waals forces!
so you're calling a hydrogen bond a van der waal's force too? "all intermolecular forces are collectively known as Van der Waal's forces"
and if you're righ, sorry for arguing ..guess I wasn't taught right.
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dude Im gonna kill you.. I just posted that a sec ago!
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Hahaha yea sorry. Apart from Hydrogen Bonds, the rest are known collectively as Van der Waals forcces
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yeh you're right ... so induced dipole- permanent dipole (Debyce force), permanent dipole- permanent dipole (keesom force) and instantaneous dipole-induced dipole (london force) are all Van der Waal'sHahaha yea sorry. Apart from Hydrogen Bonds, the rest are known collectively as Van der Waals forcces
This is what happens when you read your notes after a year and misinterpret them xD
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Yup they are Van der Waals! Hahaha well ure not the only one who's been there!
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studying for chemistry is the most boring out of all my subjects =_=
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Because the oxidation number of Cl in PCl3 is -3 and since PCl3 is neutral over all... P has to have the oxidation no. +3 to cancel out the -3 and the over all oxidation state of PCl3 can be zero. (-3+3=0)
The oxidation no. of Cl2 in SCl2 is -2 so for the entire charge to be zero S will have the oxidation number +2. (-2+2=0)
really thank u sooo much..this is so appreciated
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^thats right.
To find the oxidation state always make an equation. For example NH3. The overall charge is 0 and you have to find the oxidation number of nitrogen. hence let the oxidation number of nitrogen be x. Oxidation number of hydrogen is +1 and there are 3 atoms in total. so X+ ( 1 x 3)=0. therefore X=-3. The oxidation value of nitrogen will be -3. For NH4+ the oxidation number of nitrogen will be calculated by X+(1 x 4)= +1, hence X= -3
To find the oxidation state always make an equation. For example NH3. The overall charge is 0 and you have to find the oxidation number of nitrogen. hence let the oxidation number of nitrogen be x. Oxidation number of hydrogen is +1 and there are 3 atoms in total. so X+ ( 1 x 3)=0. therefore X=-3. The oxidation value of nitrogen will be -3. For NH4+ the oxidation number of nitrogen will be calculated by X+(1 x 4)= +1, hence X= -3
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