What does it mean for an element to undergo transmutation

Suppose you got a low yield of benzoin from your benzoin condensation reaction and thus only have 0.300 g of benzoin to use as the starting material for this reaction. how much concentrated nitric acid should you add? (concentrated nitric acid is 15.8 m). write your answer in the form x.xx ml

7. what temperature is need to just dissolve 50 g of nh4cl in 75 g of water? '

What is the mass of 0.46 mol of mgcl2