Flashcards: Electrochemical Redox Reactions — 24 cartões

Electrolysis — electrode reactions?

Pb²⁺ reduced at cathode; water oxidized at anode.

Lead nitrate solution — ions?

Contains Pb²⁺ and NO₃⁻ ions.

Electrolysis — product at cathode?

Metallic lead (Pb).

Electrolysis — product at anode?

Oxygen gas (O₂).

Small angle approximation — sin θ?

Approximately equal to θ (radians).

Small angle approximation — cos θ?

Approximately 1 - θ²/2.

Radioactive decay law — activity?

Decreases exponentially over time.

Half-life — definition?

Time for activity to halve.

Radioactive decay — units of activity?

Becquerels (Bq), decays per second.

RC circuit — voltage during charging?

u_C(t) = A(1 - e^(-t/τ)).

RC circuit — time constant?

τ = R×C, time to reach 63.2% voltage.

Damped RLC oscillations — energy?

Decreases over time due to resistance.

Sustained oscillations — energy source?

External voltage proportional to current.

Lorentz force — formula?

F = q(v × B).

Particle in magnetic field — trajectory?

Radius depends on charge, mass, velocity, magnetic field.

Particle trajectory — radius relation?

R ∝ m/(qB) for same velocity.

Pendulum — small oscillations energy?

E ≈ mgh + (1/2)Iω².

Maximum angular displacement?

From energy conservation, where kinetic energy is zero.

Potential vs kinetic energy?

Potential energy maximum at amplitude; kinetic maximum at equilibrium.

Titration — equivalence point?

pH change is steep; indicator chosen accordingly.

Indicator — selection criterion?

Range includes pH at equivalence point.

Particle identification — in magnetic field?

Compare trajectory radii; relates to mass/charge ratio.

Pendulum — small angle approximation?

sin θ ≈ θ; cos θ ≈ 1 - θ²/2.

Fusion reaction — products?

Helium nucleus (4He) and neutron.