Answer:
6.38×10²¹ molecules
Explanation:
Formula for molybdenum chloride is:
Mo₂Cl₁₀
Molar mass is : (Molar mass for Mo) . 2 + (Molar mass for Cl) . 10
95.94 . 2 + 35.45 . 10 = 546.38 g/mol
We determine moles that are contained in 5.790 g of Mo₂Cl₁₀
5.790 g . 1 mol /546.38 g = 0.0106 moles
We count the molecules: 0.0106 mol . 6.02×10²³ molecules / mol =
6.38×10²¹ molecules
Remember that 6.02×10²³ is also called Avogadro's number (NA) which is the number of particles of anything, that are contained in 1 mol.
It seems to overall decrease.
Decomposition and synthesis is the answer
Answer:
MnCO3 + 2H2O ⇄ MnO2 + HCO3- + 2e- +3H+
Explanation:
<u>The</u> unbalanced equation
MnCO3 ⇄ MnO2 + HCO3-
In MnCO3, the oxidation number of Mn is +2
In Mno2, the oxidation number of Mn is +4
The change from +2 to +4 requires an addition of 2 electrons (to the right side).
MnCO3 ⇄ MnO2 + HCO3- + 2e-
The total charge now is -3 on the right side. To balance this we add 3 hydrogen atoms on the right side.
MnCO3 ⇄ MnO2 + HCO3- + 2e- +3H+
On the right side we have 4 hydrogen atoms in total. On the left side we have 0 hydrogen atoms. So to balance, we have to add 2H2O on the left side
MnCO3 + 2H2O ⇄ MnO2 + HCO3- + 2e- +3H+
Now the reaction is balanced.
