Write a balanced equation for each of the following nuclear reactions: (a) mercury-180 decays into platinum-176 (b) zirconium-90 and an electron are produced by the decay of an unstable nucleus (c) thorium-232 decays and produces an alpha particle and a radium-228 nucleus, which decays into actinium-228 by beta decay (d) neon-19 decays into fluorine-19

Explanation:

(a) Hg-180 to Pt-176

The unbalanced nuclear equation is

It is convenient to replace the question mark by an atomic symbol, , where x = the atomic number, y = the mass number, and Z = the symbol of the element .

Then your equation becomes

The main point to remember in balancing nuclear equations is that the sums of the superscripts and the sums of the subscripts must be the same on each side of the equation.  

Then

 80 =  78 + x, so x = 2

180 = 176 + y, so y =180 - 176  = 4

Element 2 is helium, so the nuclear equation becomes

A helium nucleus is also called an alpha particle, so this reaction is an example of alpha decay.

(b) Production of Zr-90 and an electron

x = 40 - 1 = 39

y = 90 + 0 = 90

The balanced nuclear equation is

(c) Th-232 to Ra-228 to Ac-228

(d) Ne-19 to F-19

10 = 9 + x, so x = 1

19 = 18 + y , so y = -1

The balanced nuclear equation is

here is table 2-2:

country

percent of eligible voters that voted

rank

united states

44.9%

138

canada

60.1%

107

costa rica

84.6%

14

hungary

66.9%

82

japan

57.0%

118

egypt

27.7%

159

south africa

85.5%

10

ans is no, the data set cannot be plotted as a single circle graph