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Chemistry: Post your doubts here!

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I want exact definitions of relative atomic, isotopic, molecular and formula
masses, based on the 12C scale the way is should be answered ASAP! Thanks in advance
http://www.chemguide.co.uk/CIE/ exactly as the syllabus !

The relative atomic mass of an element is the weighted average of the masses of its isotopes on a scale on which a carbon-12 atom has a mass of exactly 12 units.

The relative isotopic mass of an isotope is the mass of the isotope on a scale on which a carbon-12 atom has a mass of exactly 12 units.

The relative molecular mass of a substance is the weighted average of the masses of the molecules on a scale on which a carbon-12 atom has a mass of exactly 12 units.

The relative formula mass of a substance is the weighted average of the masses of the formula units on a scale on which a carbon-12 atom has a mass of exactly 12 units.
 
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Could anyone please tell for paper 5 what construction lines are and how to construct them?
And can anyone solve M/J 08 Q2.(f) please. So I get an idea on how to solve questions like these.
Thank You! ☺
 
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Could anyone please tell for paper 5 what construction lines are and how to construct them?
And can anyone solve M/J 08 Q2.(f) please. So I get an idea on how to solve questions like these.
Thank You! ☺
The red lines are construction line ( what i learned)
 

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http://www.chemguide.co.uk/CIE/ exactly as the syllabus !

The relative atomic mass of an element is the weighted average of the masses of its isotopes on a scale on which a carbon-12 atom has a mass of exactly 12 units.

The relative isotopic mass of an isotope is the mass of the isotope on a scale on which a carbon-12 atom has a mass of exactly 12 units.

The relative molecular mass of a substance is the weighted average of the masses of the molecules on a scale on which a carbon-12 atom has a mass of exactly 12 units.

The relative formula mass of a substance is the weighted average of the masses of the formula units on a scale on which a carbon-12 atom has a mass of exactly 12 units.
Aah, thank you very much! :D
 
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Can I get the link to the page or can any1 upload the organic chemistry reactions summarised in a single diagram
Here, I wrote this mnemonic down. you can decide which ones are in AS or A2...hopefully.
If you don't understand it, please let me know :)
I'll be happy to help.
 

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hey everyone , please I have a doubt in p1 year 2002 MAY/JUNE , question 6 , I haven't got a clue how to solve it , can any one please help me out?
 
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hey everyone , please I have a doubt in p1 year 2002 MAY/JUNE , question 6 , I haven't got a clue how to solve it , can any one please help me out?
alright see do uk the formula v1p1 = v2p2 ( we took that in IG physics)

before we connect the flasks we have 2(1) + 2(1) = v2p2 ( v2p2 are the values of the volume and pressure of gasses after connecting the flasks) when we connect the flasks the volume (v2) will be 1+2 =3

so 2(1)+2(1) = 3p2
p2 = 4/3 therefore the answer is A..did u get it ?
 
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CAN YOU TELL ME REACTIONS OF GROUP II AND PERIOD III WITH HCL AND H2O AND THEIR PH AND OBSERVATION IT IS CONFUSING
 
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CAN YOU TELL ME REACTIONS OF GROUP II AND PERIOD III WITH HCL AND H2O AND THEIR PH AND OBSERVATION IT IS CONFUSING
 
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