<span>Answer:
The half-reaction is as followed:
Cr2O72â’(aq) + 14H+ + 6e⒠→ 2Cr3+(aq) + 7H2O
From the half-reaction, you can retrieve the following information:
1 mole of potassium dichromate =6 moles of e^-
6 moles of e^-=2 moles of Cr
You will also need the following information:
1 mole of e^-=96,485 C
and
1 mole of Cr=52.00g
Calculate the number of moles that 4.94mg equates too:
4.94 mg=4.94 x 10^-3g of chromium*(1 mol/52.00g)=9.50 x 10^-5 mole of Cr
How many moles of electrons are need to produce 9.50 x 10^-5 mole of Cr? Solve for moles of electrons:
9.50 x 10^-5 mole of Cr*(6 moles of e^-/2 mole of Cr)=2.85 x 10^-4 moles of e^-
Whats the charge of 2.85 x 10^-4 moles of electrons? Use Faraday's constant:
2.85 x 10^-4 moles of e^-*(96,485 C/1 mole of e^-)=2.750 x 10^1 C
Since current (A)=charge (C)/time (s), solve for time:
A=C/s
C/A=s
2.750 x 10^1 C/0.234 A=time (s)
1.18 x 10^2 s=118s=time <= 3 significant figures</span>
Answer:
The new volumen of the solution is 500 ml.
Explanation:
A dilution consists of the decrease of concentration of a substance in a solution (the higher the volume of the solvent, the lower the concentration).
We use the formula for dilutions:
C1 x V1 = C2 x V2
V2= (C1xV1)/C2
V2= (400 ml x 2,5 M)/2,0M
<em>V2= 500 ml</em>
Answer:
43.93 g/mol
Explanation:
The mass of the gas before reaction = 52.1487 g
The mass of the gas after reaction = 52.1098 g
Mass of gas generated = 0.0389 g
Moles of the gas = 
The formula for the calculation of moles is shown below:
Thus,
Molar mass of the gas = 43.93 g/mol
Answer:
Jupiter
Explanation:
Fifth in line from the sun, Jupiter is, by far, the largest planet in the solar system.
I don’t know what you mean by classification exactly but it is a redox equation. The reactant side of carbon is losing hydrogen to form carbon dioxide. And oxygen is gaining hydrogen which gives you the water. Redox reactions are also known as combustion reactions.
