Answer:
b) 2.0 mol
Explanation:
Given data:
Number of moles of Ca needed = ?
Number of moles of water present = 4.0 mol
Solution:
Chemical equation:
Ca + 2H₂O → Ca(OH)₂ + H₂
now we will compare the moles of Ca and H₂O .
H₂O : Ca
2 : 1
4.0 : 1/2×4.0 = 2.0 mol
Thus, 2 moles of Ca are needed.
Answer:
K = 2.96x10⁻¹⁰
Explanation:
Based on the initial reaction:
N2O4 ⇄ 2NO2; K = 1.5x10³
Using Hess's law, we can multiply this reaction changing K:
3 times this reaction:
3N2O4 ⇄ 6NO2; K = (1.5x10³)³ =3.375x10⁹
The inverse reaction has a K of:
6NO2 ⇄ 3N2O4 K = 1/3.375x10⁹;
<h3>K = 2.96x10⁻¹⁰</h3>
The two forms of oxygen, O2 and O3 is "<span>They have different molecular structures and different properties."</span>
First there is a need to calculate the molar mass of Ba(NO₃)₂:
137.3 + 2 (14.0) + 6 (16) = 261.3 grams/mole
The molar mass, denoted by M in chemistry refers to a physical characteristic illustrated as the mass of a given component divided by the amount of the component. The molar masses are always denoted in grams/mole.
After finding the molar mass, the number of moles can be identified as:
432 grams / 261.3 g/mol = 1.65 moles of Ba(NO₃)₂.