The answer is (3). The reaction that can occur at the anode is oxidation reaction which will lose electrons. So (1) and (2) are not correct. For (4) Fe3+ can not lose electrons again.
Answer:
The Aufbau Principle
Explanation:
In the ground state of an atom or ion, electrons fill atomic orbitals of the lowest available energy level before occupying higher-energy levels.
Ni(OH)2+H2SO4=NiSO4+2H2O
Double Replacement Reaction
Answer:
.224 M
Explanation:
To begin, we need to find the molar mass of Na2S
To find Molarity, we use the equation M=moles/Liters of solution
We are given grams, so we must divide by the molar mass of Na2S to find moles.
- 8.76g Na2S / 78.05g/mol Na2S= .112 moles
Now we use our Molarity equation:
- .112 moles Na2S / .500L of solution = .224 M
Answer:
(a) 77.9 g/mol
(b) 3.18 g / L
Explanation:
<u>(a)</u> We need to use the ideal gas law, which states: PV = nRT, where P is the pressure, V is the volume, n is the moles, R is the gas constant, and T is the temperature in Kelvins.
Notice that we don't have moles; we instead have the mass. Remember, though that moles can be written as m/M, where m is the mass and M is the molar mass. So, we can replace n in the equation with m/M, or 21.3/M. The components we now have are:
- P: 0.880 atm
- V: 7.73 Litres
- n: m/M = 21.3 g / M
- R: 0.08206
- T: 30.00°C + 273 = 303 K
Plug these in:
PV = nRT
(0.880)(7.73) = (21.3/M)(0.08206)(303)
Solve for M:
M = 77.9 g/mol
<u>(b)</u> The equation for the molar mass is actually:
M = (dRT)/P, where d is the density
We have all the components except d, so plug them in:
77.9 = (d * 0.08206 * 298) / 1
Solve for d:
d = 3.18 g / L
