A SAMPLE OF ANTIMONY, Ar=121.8, WAS ANALYSED AND WAS FOUND TO CONSIST OF 60% OF 121Sb AND ONE OTHER ISOTOPE. DETERMINE THE MASS NUMBER OF THE OTHER ISOTOPE IN THE SAMPLE OF ANTIMONY.

please help I'm really stuck,

Chemistry - bobpursley Saturday, September 30, 2017 at 10:41am
assume you have 100 grams. It becomes the overused algebra candy mixture problem.

60*121+40*X=121.8*100
solve for x

Chemistry - Dannau Saturday, January 6, 2018 at 7:01am
Thats wrong. The answer is 123

Chemistry - 0oooooooo0 today at 6:35am
How do you get that though

As chemistry - 0oooooooo0 Thursday, March 1, 2018 at 6:37am
I read somewhere the right answer is 123 but dont know how to get it and I tried Bobpursley equations but go -151.05 so I think that working out is wrong. Please help someone

1 answer

Chemistry - bobpursley Saturday, September 30, 2017 at 10:41am
assume you have 100 grams. It becomes the overused algebra candy mixture problem.

60*121+40*X=121.8*100
solve for x

I am just a bit miffed: Here is what I told you to do:
60*121+40*X=121.8*100
40x=12180-7260=4920
x=123
You need to do some introspection: what is going wrong with you? Is it math? Is it you have became addicted to getting answers handed to you? Something is seriously wrong, and only you can figure it out.