Answer:
Na3PO4 is excess reactant, CaCl2 is limiting reactant.
Explanation:
3CaCl2 + 2Na3PO4 ---> Ca3(PO4)2 + 6NaCl
from reaction : 3 mol 2 mol
given: 6 mol 5 mol (X)
X = (6*2)/3 = 4 mol Na3PO4
For 6 mol CaCl2 we need 4 mol Na3PO4, but we have 5 mol Na3PO4,
Na3PO4 is excess reactant, so CaCl2 is limiting reactant.
0.042 moles of Hydrogen evolved
<h3>Further explanation</h3>
Given
I = 1.5 A
t = 1.5 hr = 5400 s
Required
Number of Hydrogen evolved
Solution
Electrolysis of water ⇒ decomposition reaction of water into Oxygen and Hydrogen gas.
Cathode(reduction-negative pole) : 2H₂O(l)+2e⁻ ⇒ H₂(g)+2OH⁻(aq)
Anode(oxidation-positive pole) : 2H₂O(l)⇒O₂(g)+4H⁻(aq)+4e⁻
Total reaction : 2H₂O(l)⇒2H₂(g)+O₂(g)
So at the cathode H₂ gas is produced
Faraday : 1 mole of electrons (e⁻) contains a charge of 96,500 C

Q = i.t
Q = 1.5 x 5400
Q = 8100 C
mol e⁻ = 8100 : 96500 = 0.084
From equation at cathode , mol ratio e⁻ : H₂ = 2 : 1, so mol H₂ = 0.042
A scientist would most likely need to update her model when it no longer supports the latest results.
Answer:

Explanation:
Hello,
In this case, since the given 5-M concentration of magnesium chloride is expressed as:

We can notice that one mole of salt contains two moles of chloride ions as the subscript of chlorine is two, in such a way, with the volume of solution we obtain the moles of chloride ions as shown below:

Best regards.