Q2Q - Mass Defect (1 Viewer)

Tha Wishkah

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How many people managed to get it to be 0.097?

We were taught to exclude the electrons, thus we (whole cohort) could only show it was equal to 0.094. I'd imagine if you included the electrons in the defect however, you would get 0.097amu

How many marks would i expect to lose for not taking into account the electrons?

=. ="
 

samwell

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Tha Wishkah said:
How many people managed to get it to be 0.097?

We were taught to exclude the electrons, thus we (whole cohort) could only show it was equal to 0.094. I'd imagine if you included the electrons in the defect however, you would get 0.097amu

How many marks would i expect to lose for not taking into account the electrons?

=. ="
i got it lol
u might loose only one provided that u showed how u got everything else.

EDIT: i considered electrons too.
 

pdoueihi

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all u needed to do was use the 1amu = something kg.... on the data sheet divide ur mass by this number to convert to amu
 

Tha Wishkah

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pdoueihi said:
all u needed to do was use the 1amu = something kg.... on the data sheet divide ur mass by this number to convert to amu
no i did this, just couldnt get it to be 0.097, only 0.094

was thinking my calculator was broken cause i put it through like 5 or 6 times checking i hadn't misplaced a decimal or something
 

duy.le

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Tha Wishkah said:
no i did this, just couldnt get it to be 0.097, only 0.094

was thinking my calculator was broken cause i put it through like 5 or 6 times checking i hadn't misplaced a decimal or something
HOLy, y didnt i think of the electron. yeah i only got 0.094.
 

Kearnzo

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Yes, it was weird. Electrons can be disregarded when you are calculating the binding energy of the nucleus, and when doing calculations on the mass difference in transmutations.

I would like to know whether electrons are included in the periodic table to give the 12 amus for carbon.

Meh. I had time to figure out what they were trying to do though.
 

old.skool.kid

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Yer this question took me ages, at first i didnt include the electron but it didnt seem right and then i used the electrons and it was right except it had more decimal places. Did anyone else get this?
 

hodarrenkm

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i dont think the 12 amu for carbon includes electrons
it even assumes that protons and neutrons have the same mass
the question was so weird
 

Js^-1

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Yeh I had the more decimal places thing, but you took it to three decimal places because that's what they give you the mass of carbon to, i.e. 12.000.
I'm pretty sure the 12.000 amu for carbon includes the electrons. Isn't the amu system defined by Carbon having 12.000 amu?
 

kangms

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lol..i got around 12.0095 for the thing but i didnt write that in the paper. I just wrote the working out (6proton+6electron+6neutron) and i just wrote that they equal to 12.0097...you can't argue with the stuff they give you so i just agreed with the question
 

moderf

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i thought electrons were not included either, but it only worked if electrons were to included
 

Pwnage101

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it said 'the mass of the carbon ATOM is 12.00', whatever u were taught dude, its well ddocumented in etxtbooks that if it says 'nucleus'-exclude electron, and if it says 'atom' - include atom

plus they were kind enuff to give u the answer so how could u go wrong??
 

Pwnage101

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kangms said:
lol..i got around 12.0095 for the thing but i didnt write that in the paper. I just wrote the working out (6proton+6electron+6neutron) and i just wrote that they equal to 12.0097...you can't argue with the stuff they give you so i just agreed with the question
...get a data sheet and do the working now, pretty easy...
 

Propadanda

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Yeah srsly, if you weren't getting the right answer, why didn't you just include the electrons, like if you checked your calculations and they were wrong ehh.

And it was the whole atom yeah.
 

loathi

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Pwnage101 said:
...get a data sheet and do the working now, pretty easy...
6*(1.675*10^-27/1.661*10^-27) + 6*(1.673*10^-27/1.661*10^-27) - (12.0000 - 9.109*10^-31/1.661*10^-27)

= 0.097 approx
 
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Shadose

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data here:
6 protons = 6 x 1.6736^-27
6 neutrons = 6 x 1.675^-27
6 electrons = 6 x 9.109^-31
total= 6 x 1.6736^-27 + 6 x 1.675^-27 + 9.109^-31 = ???

12.000 - ???=0.097... (I did to 3 decimal places)
which is approximately 0.097
 
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loathi

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Shadose said:
data here:
6 protons = 6 x 1.6736^-27
6 neutrons = 6 x 1.675^-27
6 electrons = 9.109^-31
total= 6 x 1.6736^-27 + 6 x 1.675^-27 + 9.109^-31 = ???

12.000 - ???=0.097... (I did to 3 decimal places)
which is approximately 0.097
Incorrect.

6 electrons = 6*9.109*10^-31
 

Artemis.

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Yeah I got the 0.094 as well, might lose a mark or so but close enough lol.
 

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