441 g CaCO₃ would have to be decomposed to produce 247 g of CaO
<h3>Further explanation</h3>
Reaction
Decomposition of CaCO₃
CaCO₃ ⇒ CaO + CO₂
mass CaO = 247 g
mol of CaO(MW=56 g/mol) :

From equation, mol ratio CaCO₃ : CaO = 1 : 1, so mol CaO :

mass CaCO₃(MW=100 g/mol) :

I would personally convert the 12 mg to g so I could see what I was working with. So 12 mg to grams is 0.012 g...
so 1 tablet is 0.012g. the patient needs 0.024 g.
so 0.024g/0.012g = 2 tablets or 0.012g X 2 is 0.024 g
hope this helps :)
Reactant C is the limiting reactant in this scenario.
Explanation:
The reactant in the balanced chemical reaction which gives the smaller amount or moles of product is the limiting reagent.
Balanced chemical reaction is:
A + 2B + 3C → 2D + E
number of moles
A = 0.50 mole
B = 0.60 moles
C = 0.90 moles
Taking A as the reactant
1 mole of A reacted to form 2 moles of D
0.50 moles of A will produce
= 
thus 0.50 moles of A will produce 1 mole of D
Taking B as the reactant
2 moles of B reacted to form 2 moles of D
0.60 moles of B reacted to form x moles of D
= 
x = 2 moles of D is produced.
Taking C as the reactant:
3 moles of C reacted to form 2 moles of D
O.9 moles of C reacted to form x moles of D
= 
= 0.60 moles of D is formed.
Thus C is the limiting reagent in the given reaction as it produces smallest mass of product.
The answer to “most of the energy released by nuclear fission in the form of _____ rays.” is GAMMA RAYS