Edexcel CHEMISTRY DOUBTS!!!!

[raimunts]

first you find the number of moles:

mass/mr of iodine molecules,

the multiply by 2 because there are 2 iodine atoms in each mole.

the 2 cancels out with the Mr.

What do you mean by the 2 cancels out with the Mr? This is the calculation I made:
(0.025/126.9) * 2 * Avogadro's constant
How does the 2 get divided?

[Kim]

What do you mean by the 2 cancels out with the Mr? This is the calculation I made:
(0.025/126.9) * 2 * Avogadro's constant
How does the 2 get divided?

i dont get it why are u guys multiplying by 2?
there is no 2 in the question

[Dento]

are halogenoalkanes and their reactions in unit 1? or in unit 1 organic we must only know about alkanes, alkenes, alcohols, etc

[Kim]

are halogenoalkanes and their reactions in unit 1? or in unit 1 organic we must only know about alkanes, alkenes, alcohols, etc

in unit 1 organic u only need to know about alkanes alkenes and alcohols

[Dento]

thanks kim, i appreciate the early reply on such an early morning, ;0

[Kim]

thanks kim, i appreciate the early reply on such an early morning, ;0

its not early
its 12 in the afternoon where i am

[Dento]

well its 11 here so i thought chemistry students might be sleeping as unit 1 is today PM timing

[Ibiza279]

i don't get Raimunts post about the iodine atoms question, i mean Iodine exists as I2 rite, but when u see the mark scheme, if u multiply 126.9 X 2, ur doin it the wrong way, can some one explain it to me plz, the logic me n a buddy of mine made of it was that Iodine exists as a mono atomic substance in the body as part of some compound so it would exist as an Ion, so v use only 126.9, can some one enlighten me plzzz !!!!!

[Kim]

well its 11 here so i thought chemistry students might be sleeping as unit 1 is today PM timing

haha nice
i have to leave in about 2 and half hours
so wont sleep

[Kim]

i don't get Raimunts post about the iodine atoms question, i mean Iodine exists as I2 rite, but when u see the mark scheme, if u multiply 126.9 X 2, ur doin it the wrong way, can some one explain it to me plz, the logic me n a buddy of mine made of it was that Iodine exists as a mono atomic substance in the body as part of some compound so it would exist as an Ion, so v use only 126.9, can some one enlighten me plzzz !!!!!

well wat i think because they say to find the no of atoms so u divide the moles by the mass of an iodine atom and then multiply by the avogadro constant to get the no of atoms

[Ibiza279]

well wat i think because they say to find the no of atoms so u divide the moles by the mass of an iodine atom and then multiply by the avogadro constant to get the no of atoms

but then as u say it in the Volume question in which flourine is used, why do v take its mass number X 2 while here we jus take the mass number ? 

[Kim]

but then as u say it in the Volume question in which flourine is used, why do v take its mass number X 2 while here we jus take the mass number ? 

which question is dat???

[Ibiza279]

which question is dat???

its one of Raimunts posts, a page bak, also one of the mcqs of June 09, 17th i think.

[Kim]

its one of Raimunts posts, a page bak, also one of the mcqs of June 09, 17th i think.

that is adifferent question u have to calculate tyhe volume for dat so u calculate using f2
but for this u r calculating atoms and in the periodic table the masses are of atoms so u directly use dat mass

[Ibiza279]

also, could u tell me the trends in solubility of the group 1 and 2 metals, also the trend relating to the hydration enthalpy and lattice enthalpy and its explanation plz