How many grams of sodium azide, NaN3, are needed to produce 84 g of N2 (g) ? MM (N2) = 28 g/mol MM(NaN3) = 65.0 g/mol 2NaN3 (s) 3N2 (g) + 2Na (s)

Alpha particles have positive charge, beta particles have negative charge, and answer 4 just doesn’t make sense. thus, you are left with only one possible answer.

Exothermic,  physical change after it is already baked

It is a product

Aquantity of that isotope to decay to 1/2 of  its original value