Chemistry Questions

[Blinx]

I am really really stuck with this Chemistry question.
Is there any chance someone can guide me through it?

4. The relative atonic mass of the element iridium is 192.2. Iridim occurs naturally as a mixture of iridium-191 and iridium-193. Work out the percentage of each isotope in naturally occurring iridium by the following steps.

a ) If the percentage of iridum-193 in naturally occouring iridium is x%, there must be x atoms of iridium-193 in every 100 atoms of the element. How many atoms of iridium-191 therefore, must there be in every 100 atoms of iridium?

So logically. If Iridium 193 is equal to x%, then Iridium 191 should be equal to y%?

B) What will be the total relative mass of the atoms of iridum-193 in the 100 atom sample?
This is where I get confused.
Is the total relative mass equal to 192.2/191 = 1.00?
Or is it something more complex?

Any help would be appreciated guys! :D I'm not asking you to do my homework for me. I'm just wondering if you could give me a helping hand with it. :)

[Slick]

Well I would have to say the answer is*brain explodes*

[Pigbuster]

I'm so glad I never have to deal with chemistry again.

Yes, there is no point to this post. :p

[SomePerson]

I am really really stuck with this Chemistry question.
Is there any chance someone can guide me through it?

4. The relative atonic mass of the element iridium is 192.2. Iridim occurs naturally as a mixture of iridium-191 and iridium-193. Work out the percentage of each isotope in naturally occurring iridium by the following steps.

a ) If the percentage of iridum-193 in naturally occouring iridium is x%, there must be x atoms of iridium-193 in every 100 atoms of the element. How many atoms of iridium-191 therefore, must there be in every 100 atoms of iridium?

So logically. If Iridium 193 is equal to x%, then Iridium 191 should be equal to y%?

B) What will be the total relative mass of the atoms of iridum-193 in the 100 atom sample?
This is where I get confused.
Is the total relative mass equal to 192.2/191 = 1.00?
Or is it something more complex?

Any help would be appreciated guys! :D I'm not asking you to do my homework for me. I'm just wondering if you could give me a helping hand with it. :)

wouldn't Iridium 191 be (100-x)%?

wouldn't it be (191*x/100 + 193*(100-x)/100) = average mass of iridium solve for x? Or do I not get what you mean?

[MrBunsy]

Funnily enough, I just dropped Chemistry last week, but I still got an A at AS so I feel like I ought to know something.
I am really really stuck with this Chemistry question.
Is there any chance someone can guide me through it?

4. The relative atonic mass of the element iridium is 192.2. Iridim occurs naturally as a mixture of iridium-191 and iridium-193. Work out the percentage of each isotope in naturally occurring iridium by the following steps.

a ) If the percentage of iridum-193 in naturally occouring iridium is x%, there must be x atoms of iridium-193 in every 100 atoms of the element. How many atoms of iridium-191 therefore, must there be in every 100 atoms of iridium?

So logically. If Iridium 193 is equal to x%, then Iridium 191 should be equal to y%?I'd have though 100-x would be more logical, since then you've only got one unknown to deal with.

B) What will be the total relative mass of the atoms of iridum-193 in the 100 atom sample?
This is where I get confused.
Is the total relative mass equal to 192.2/191 = 1.00?
Or is it something more complex? I'm not sure about the term total relative mass, but I assume it's what I'd call Relative Atomic Mass? In which case the answer to the question is algebra, not chemistry :confused:

Anyways, since I normally work out RAM along the lines of:

((% isotope1 X RAM isotope1)+(% isotope2 X RAM isotope2)+...)/100 = RAM

if you use the 100-x then you can subsitute everything in to the above equation, and only have one variable to find, which will be the answer to the question. I think.

edit: Aw phoot, you beat me to it :p , but that's what I was thinking too.

[bonz]

I am really really stuck with this Chemistry question.
Is there any chance someone can guide me through it?

4. The relative atonic mass of the element iridium is 192.2. Iridim occurs naturally as a mixture of iridium-191 and iridium-193. Work out the percentage of each isotope in naturally occurring iridium by the following steps.

a ) If the percentage of iridum-193 in naturally occouring iridium is x%, there must be x atoms of iridium-193 in every 100 atoms of the element. How many atoms of iridium-191 therefore, must there be in every 100 atoms of iridium?

So logically. If Iridium 193 is equal to x%, then Iridium 191 should be equal to y%?

B) What will be the total relative mass of the atoms of iridum-193 in the 100 atom sample?
This is where I get confused.
Is the total relative mass equal to 192.2/191 = 1.00?
Or is it something more complex?

Any help would be appreciated guys! :D I'm not asking you to do my homework for me. I'm just wondering if you could give me a helping hand with it. :)
Ad A)
http://en.wikipedia.org/wiki/Isotopes_of_iridium
Ir-191 --> 37.3%
Ir-193 --> 62.7%
Those two are the only stable ones, all others decay.

Ad B)
190.96 u * 37.3% + 192.96 u * 62.7% = 192,214 u
http://en.wikipedia.org/wiki/Atomic_mass_unit

[Blinx]

Cheers for your help guys. =]

Onto the next question. To do with Antimony. :)

I was wondering tho.
How do they synthesise elements?

[bonz]

Onto the next question. To do with Antimony.
What's the question?
How do they synthesise elements?
Either in particle accelerators by bombarding stuff or in nuclear reactors through radioactive decay.