The limiting reagent : NH₃
<h3>Further explanation</h3>
A method that can be used to find limiting reactants is to divide the number of moles of known substances by their respective coefficients, and small or exhausted reactants become a limiting reactant
Reaction
4NH₃(g)+5O₂(g)⇒4NO(g)+6H₂O(g)
mol NH₃ :
mol O₂ :
mol ratio
NH₃ :
O₂ :
Limiting reactants : NH₃ (smaller ratio)
For this, we use equations from the colligative properties of solutions specifically boiling point elevation and freezing point depression. The equations for these are expressed as:
ΔTb = kb m
where k is a boiling point elevation constant and m is the concentration in terms of molality
ΔTf = kf m
where k is a freezing point elevation <span>constant and m is the concentration in terms of molality
</span>
We use both expression to solve for the freezing point. For this case, concentration is the same. The equation will then be:
ΔTf = kf ( ΔTb / kb )
0-Tf = 1.86 (103.7 - 100 / 0.512 )
Tf = -13.4°C
Answer:
E° = 0.00 V
E = 0.079 V
Explanation:
We can identify both half-reactions occurring in a concentration cell.
Anode (oxidation): Al(s) → Al³⁺(1.0 × 10⁻⁵ M) + 3 e⁻ E°red = -1.66 V
Cathode (reduction): Al³⁺(0.100 M) + 3 e⁻ → Al(s) E°red = -1.66 V
The global reaction is:
Al(s) + Al³⁺(0.100 M) → Al³⁺(1.0 × 10⁻⁵ M) + Al(s)
The standard cell potential (E°) is the difference between the standard reduction potential of the cathode and the standard reduction potential of the anode.
E° = E°red, cat - E°red, an = -1.66 V - (-1.66 V) = 0.00 V
To calculate the cell potential (E) we have to use the Nernst equation.
E = E° - (0.05916/n) .log Q
where,
n: moles of electrons transferred
Q: reaction quotient
E = 0.00 V - (0.05916/3) .log (1.0 × 10⁻⁵/0.100)
E = 0.079 V
Volt is the unit to measure cell potential.
Explanation:
The cell potential is the measure of potential difference in the two halves of the electrochemical cell.
It is the measure of how much voltage exists between the two halves of the battery. The unit of volt is joule/coulomb. The cell potential is measured by voltmeter.
The energy per unit charge from the oxidation-reduction reaction to drive the reaction is cell potential.
