Questions regarding stoich/atomic structure

[masochist]

QUESTION ONE

Write balanced equations to represent the formation of the following compounds, starting with T2 or T20

NT3: 3T2+N2-->2NT3

NaOT: i don't know how to do this one

could some one help me out please?

T2O + 2NA ---> 2NaOt?

QUESTION TWO

Chlorine exists as two isotopes, Cl-35 and Cl-37. The ram of chlorine is 35.45 Calculate the percentage abundance of each isotope.

[IBer_101]

What's T? You mean H??

As for your second question,

Take X to be the percentage abundance of Cl-35

Hence,

[ (X/100) * 35 ] + [ ( (100-X)/100 ) * 37 ] = 35.45

Solve the equation (using GDC or otherwise):

X = 77.5%

So, % abundance of Cl-35 is 77.5%

% abundance of Cl-37 is (100 - 77.5) = 22.5%

Edited May 17, 2010 by IBer_101

[Kaneele]

Won't be able to help you out with the first one. But really - do you probably mean tritium with that T - which is an isotope of H with mass number 3?

However, I might be able to provide a formula for the second one, mate

As far as I am concerned, the relative atommass is A_r.

Then the formula is A_r=w₁*A_r1+w₂*A_r2...+w_n*A_rn

where A_r1 is the isotope's atommass (the upper number in the periodic table) - in this occasion you have two different ones and w - the abundance of the isotope.

Now, all you have to do is consider that the total abundance for both of them equals 100% or 1, therefore do some arithmetic transifgurations with the equation and you should arrive at the answer pretty quickly.

Hope it helped!

P.S. Ah, fail, Mr IBer managed to write it before me

All the best,

Kaneele

Edited May 17, 2010 by Kaneele

[IBer_101]

Your post is a more detailed explanation than mine of the theory involved, no worries

[masochist]

Thank you very much.

With regards to the first question, the T is tritium.

[IBer_101]

Doesn't Tritrium have the same chemical properties as Hydrogen, since it only differs by the number of neutrons?

Anyways, if you want to form the Hydroxide of an alkali metal or alkali earth metal, you react the metal with water (the only exception being Mg which only reacts with water vapour at high temperature to produce the metal oxide and Hydrogen gas):

2 Na_(s) + 2 H₂O_(l) --> 2 NaOH_(aq) + H_2(g)