Answer:

Explanation:
The unbalanced nuclear equation is

Let's write the question mark as a nuclear symbol.

The main point to remember in balancing nuclear equations is that the sums of the superscripts and the subscripts must be the same on each side of the equation.
Then
98 = 0 + A, so A = 98 - 0 = 98, and
38 = -1 + Z, so Z = 38 + 1 = 39
Then, your nuclear equation becomes

Element 39 is yttrium, so the balanced nuclear equation is

Answer:
Precautions
Explanation:(Grammar Check)
Ans: 15.1 grams
Given reaction:
Na2CO3 + Ca(OH)2 → 2NaOH + CaCO3
Mass of Na2CO3 = 20.0 g
Molar mass of Na2CO3 = 105.985 g/mol
# moles of Na2CO3 = 20/105.985 = 0.1887 moles
Based on the reaction stoichiometry: 1 mole of Na2CO3 produces 2 moles of NaOH
# moles of NaOH produced = 0.1887*2 = 0.3774 moles
Molar mass of NaOH = 22.989 + 15.999 + 1.008 = 39.996 g/mol
Mass of NaOH produced = 0.3774*39.996 = 15.09 grams
Answer:
did you mean to add or attach a paper to this? We need more info to help
Explanation: