Solutions: Atomic Structure
Q8.
(a) Name the constituent of an atom which
(i) has zero charge,
neutron
(ii) has the largest charge to mass ratio,
electron
(iii) when removed leaves a different isotope of the element.
neutron
(3)
(b) An
particle is the same as a nucleus of helium,
.
The equation
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represents the decay of thorium by the emission of an
particle.
Determine:
(i) the values of X and Y, shown in the equation,
X = 90 - 2 = 88
Y = 229 - 4 = 225
(ii) the ratio of the mass of the radium nucleus to the mass of the alpha particle
225/4 = 56.3
(allow C.E. for value of X from (i))
(3)
(Total 6 marks)