Question

Write a balanced nuclear equation for the positron emission of each of the following radioactive isotopes: silicon-26,mercury-188,7737Rb,9345Rh

Answer 1

Since we can't do subscripts and superscripts as we would like I do these so that the first number is the atomic number followed by the symbol of the element followed by the mass number. For example, 26Co60 is Co (element 26) with a mass number of 60. A positron is a positive electron and is +1e0 meaning +1 charge and 0 mass.
14Si26 ==> +1e0 + yXz
Now you want the atomic numbers to add up and the masses to add up.
14 = 1 + y; therefore, y must be 13. Element 13 is Al so X = Al. Then 26 = 0+z so z ust be 26. The equation is
14Si26 = 1e0 + 13Al26

The others are done the same way.