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physics question 2012 q8

aarond280 · 2013-03-13 21:03:51

http://examinations.ie/archive/markingschemes/2012/LC021ALP000EV.pdf can anyone tell me how to answer this question, question 8, where so they get ( reactants:) 2.014102 + 3.016049 / 5.030151 ( products:) 4.002603 + 1.008672 / 5.011275

13-03-2013 10:03pm

#1

aarond280

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Posts: 238

http://examinations.ie/archive/markingschemes/2012/LC021ALP000EV.pdf
can anyone tell me how to answer this question, question 8, where so they get
( reactants:) 2.014102 + 3.016049 / 5.030151
( products:) 4.002603 + 1.008672 / 5.011275

0

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#2 13-03-2013 10:37pm

borrch

Registered Users Posts: 248 ✭✭

Join Date: January 2011

Posts: 245

aarond280 wrote: »

http://examinations.ie/archive/markingschemes/2012/LC021ALP000EV.pdf
can anyone tell me how to answer this question, question 8, where so they get
( reactants:) 2.014102 + 3.016049 / 5.030151
( products:) 4.002603 + 1.008672 / 5.011275

It's the values of 2/1 H + 3/1 H, check pg83 in your log tables:)

your product values (from the periodic table - pg79) for He and H

then ... (u)(0.018875)=mass =3.1342 x 10 (-29)

so ... e=mc^2 is...

E= (3.1342 x 10 -29)(2.9979 x 10 8 squared)

Ans: 2.816878895 x 10 (-12) Joules

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