Before the discovery of the neutron, it was proposed that the penetrating radiation produced when beryllium was bombarded with alpha particles consisted of high energy gamma rays (up to 50 MeV) produced in reactions such as alpha+9 Be--->13 C+ gamma. a). Calculate the Q-value for this reaction. b). If 5 MeV alpha particles are incident on 9Be, calculate the energy f the 13C nucleus and hence, determine the energy of gamma radiation assuming it is emitted as a single photon. Hint: you may neglect the momentum of the gamma ray relative to the 13C nucleus. Masses: m (4He)= 4.0026u, m(9Be)= 9.0122u, m (13C)= 13.0034 u.

Answer part a:

Q= 10.62 MeV

Answer part b:

Energy of gamma particle is given by

E γ = 10.62 MeV

Explanation:

See attached file for explanation.

a. 0.00194 u b. 16.25 eV; 2.899 X 10^-13 J of energy released

Explanation:

4He + 9 Be -> 13 C + n

13.034-(4.0024+9.0122)=0.0194 u, 1 u = 1.66054 x10^-27

E=Δmc^2

  1.the balanced   chemical equation is as below

cu +   2 ag(no)₃ → cu(no₃)₂   +2 ag

2.the   much silver   produced   is   50.9 g

step 1: find the   moles of cu

moles =   mass÷   molar mass

  from periodic table the molar mass of cu = 63.5 g/mol

moles is therefore = 15.00 g÷ 63.5 g/mol = 0.236   moles

step 2: use the mole ratio to determine the   moles of ag

from equation above   cu: ag   is 1: 2

therefore the moles of ag   =0.236   moles   x 2/1 =0.472   moles

step 3: find the mass   of ag

mass = moles x molar mass

from periodic table   the molar mass of ag =107.87 g/mol

mass   = 0.472   moles x 107.87 g/mol = 50.9 g

3.   the   much   silver   collected worth is   1.797 oz

  convert   50.9 g   to oz

that is   1 gram = 0.0353 oz

          50.9 grams =?   oz

by cross multiplication

={(50.9 grams x 0.0353 oz) / 1   gram}   =1.797 oz

answergravity;