Answer:
145.8g
Explanation:
Given parameters:
Number of moles of magnesium hydroxide = 2.5mol
Unknown:
Mass of Mg(OH)₂ = ?
Solution:
To solve this problem we use the expression below;
Mass of Mg(OH)₂ = number of moles x molar mass
Molar mass of Mg(OH)₂ = 24.3 + 2(16 + 1) = 58.3g/mol
Mass of Mg(OH)₂ = 2.5 x 58.3 = 145.8g
<span>40 20Ca this is the appropriate symbol for an isotope of calcium-42 corresponding to the isotope notation AZX</span><span />
Answer:
0.84 moles of oxygen are required.
Explanation:
Given data:
Mass of CO₂ produced = 37.15 g
Number of moles of oxygen = ?
Solution:
Chemical equation:
C + O₂ → CO₂
Number of moles of CO₂:
Number of moles = mass/molar mass
Number of moles = 37.15 g/ 44 g/mol
Number of moles = 0.84 mol
Now we will compare the moles of oxygen and carbon dioxide.
CO₂ : O₂
1 : 1
0.84 : 0.84
0.84 moles of oxygen are required.
I think it’s B 5.54 x 10^2g