Not sure how to work this out even though it's only worth one mark. Bromine has two isotopes BR-79 and Br-81 the relative atomic mass of br is 79.9 calculate the percentage of br-79 atoms in a sample of bromine.
Not sure how to work this out even though it's only worth one mark. Bromine has two isotopes BR-79 and Br-81 the relative atomic mass of br is 79.9 calculate the percentage of br-79 atoms in a sample of bromine.
This has nothing to with this, but I really want to do Chemistry next year
Not sure how to work this out even though it's only worth one mark. Bromine has two isotopes BR-79 and Br-81 the relative atomic mass of br is 79.9 calculate the percentage of br-79 atoms in a sample of bromine.
So you know that the average mass is 79.9, and that the two abundances add up to 100%.
From there, let x = the % abundance of BR-79. (taking 1 to be 100%)
You know then that the % abundance of BR-81 is 1-x.
From that you can get this equation:
79x+(1-x)81 = 79.9
Rearrange and you''ll end up with a decimal e.g 0.76 or something, which would mean 76%.
I recommend trying a couple questions like this to get the hang of it.
Nice and that's true, but to be honest in all fairness they are making GCSE's really hard now I'll be lucky to even get a B or an A
It's the work you put in at a level, you can be a genuis and get a D. Or you can scrape a B at gcse work so hard at as level and do every past paper and get an A. So don't be put off at ALL.
It's the work you put in at a level, you can be a genuis and get a D. Or you can scrape a B at gcse work so hard at as level and do every past paper and get an A. So don't be put off at ALL.