Question

Hi again! So, I am having trouble with this other problem that I shall put up in a few minutes. Will also show work so please tell me what exactly I'm doing wrong! Many thanks in advanced.

Answer 1

So i am trying to calculate the binding energy which I know is given by E=mc^2. So first I could out the number of neutrons and the number of protons for Sulfer which I found to be:

Neutrons: 19
Protons: 16

I then did 19(1.0087)+16(1.0073)=35.6

Then I know I am supposed to subtract this from the total mass of Sulfur which they gave me on the table as: 32.066

So I got 35.6-32.066=3.534

Then they ask for the binding energy in MeV so I know i had to multiply using the conversion factor:

3.534(931.5)=3291.921

which i know isn't the answer because it is just a huge number and I have no idea what else I'm supposed to do.

Answer 2

Many thanks in advanced!

Answer 3

Your issue is that you used the mass of the nuclide for normal Sulfur. The Sulfur here is an isotope S-35. There are 3 additional neutrons you are not accounting for. Instead of 32.066u, I believe you would want to use 34.969u.

Answer 4

I'm sorry but I am still getting an incorrect answer. Although I do understand your point.

Answer 5

Are you getting about 290-291 MeV?

Answer 6

No I am not, i keep getting some really big number ->2988.72

Answer 7

this is what i'm getting at least,

\[\Delta m = Zm_{H} + Nm_{N} - m_{Z}^{A}\]\[\Delta m = (16)(1.007276u) + (19)(1.008665u) - 34.969u = 0.312051u\]\[BE = \Delta m c^{2}=(0.312051)(931.5) = 290.7 MeV\]

Answer 8

Yes I had input that and it isn't the right answer either. I'm sorry

Answer 9

Hmm, that weird. And no need to apologize. I'm sorry I couldn't get the right thing. I can't find any flaws in the work, although it has been a few years since I calculated this stuff haha. Maybe someone will spot something.

Answer 10

Thank you though I really appreciate it :)

Answer 11

I am looking into this as I don't remember how to do it off the top of my head, but I noticed that your equations is E=mc^2 but you never squared anything. Did I miss something?

Answer 12

you factor out the c^2 and then they all cancel at the end.

Answer 13

I was basically following my professor's notes and i am doing the same exact thing he did and still nothing.

Answer 14

Ok, just checking. I will keep looking.

Answer 15

I really appreciate your help

Answer 16

From what I can tell, @Pompei00 has the right idea that you need to use the actual mass of S-35. Otherwise, it all looks right to me.

Answer 17

The only thing I can think of is rounding error. Do you know what digit you are to round to?

Answer 18

They use whole numbers for this one. I honestly do not know what I'm doing wrong...i've watched a few videos and googled everything, and nothing.

Answer 19

Ok, and you put in 291 and it was wrong?

Answer 20

I don't really see any errors either...

Answer 21

That's okay. I'll still wait and see if someone can help me with this. THank you again :)

Answer 22

Ok. No worries.

Answer 23

Since no ones getting answers you better ask your professor

Answer 24

and please tell me from where you got your screenshot

Answer 25

Haha it's okay. I'm looking over other questions as well.
I got my screen shot from my computer. I took it myself.

Answer 26

is it a software or a website from where u got your question

Answer 27

Yep. it's required for our class. I really don't like it, in my opinion. All your answers need to be put in a specific way and it's so annoying.

Answer 28

Okay then. am still trying to find the answer

Answer 29

I reallly appreciate you trying to help