Answer: limiting reactant (or limiting reagent): The reactant that determines the amount of product that can be formed in a chemical reaction.
Explanation: Your welcome buddy.
A controlled variable is essentially what is kept the same throughout the whole experiment.
No it's not a proper solution to the world's problems
There are 4 half lives of radium-226 in 6396 years. 15.0 divided by half 4 times (15.0/2= 7.5, 7.5/2 = 3.75, 3.75/2 = 1.875) equals 1.875 mg of radium-226.