The question is missing. Here is the complete question.
Which balanced redox reaction is ocurring in the voltaic cell represented by the notation of
?
(a) 
(b) 
(c)
(d) 
Answer: (d) 
Explanation: <u>Redox</u> <u>Reaction</u> is an oxidation-reduction reaction that happens in the reagents. In this type of reaction, reagent changes its oxidation state: when it loses an electron, oxidation state increases, so it is oxidized; when receives an electron, oxidation state decreases, then it is reduced.
Redox reactions can be represented in shorthand form called <u>cell</u> <u>notation,</u> formed by: <em><u>left side</u></em> of the salt bridge (||), which is always the <em><u>anode</u></em>, i.e., its half-equation is as an <em><u>oxidation</u></em> and <em><u>right side</u></em>, which is always <em><u>the cathode</u></em>, i.e., its half-equation is always a <em><u>reduction</u></em>.
For the cell notation: 
Aluminum's half-equation is oxidation:

For Lead, half-equation is reduction:

Multiply first half-equation for 2 and second half-equation by 3:


Adding them:

The balanced redox reaction with cell notation
is

Answer:
No
Explanation:
If tin is heated, it can react with alkalis' with the release of hydrogen.
Answer:
Both reaction A and reaction B are non spontaneous.
Explanation:
For a spontaneous reaction, change in gibbs free energy (
) should be negative.
We know,
, where T is temperature in Kelvin scale.
Reaction A: 
As
is positive therefore the reaction is non-spontaneous.
If at a temperature T K , the reaction is spontaneous then-

or, 
or, 
or, 
So at a temperature greater than 350 K, the reaction is spontaneous.
Reaction B: 
As
is positive therefore the reaction is non-spontaneous.
If at a temperature T K , the reaction is spontaneous then-

or, 
or, 
or, 
So at a temperature greater than -16 K, the reaction is spontaneous.
102 grams.
Equation:
Quantify of heat = mass x specific heat x difference in temperature
We have: quantity of heat : 2300J
specific heat: .449 J/g
difference in t: 80 - 30 = 50
Solve for mass: 2300 = mass x 0.449 x 50
mass = 102.449
2 sig-figs --> 102 grams
Answer:
C. 81 degrees Celsius
Explanation:
- To solve this problem, we can use the relation:
<em>Q = m.c.ΔT,</em>
where, Q is the amount of heat released from water (Q = - 1200 J).
m is the mass of the water (m = 20.0 g).
c is the specific heat capacity of water (c of water = 4.186 J/g.°C).
ΔT is the difference between the initial and final temperature (ΔT = final T - initial T = final T - 95.0°C).
<em>∵ Q = m.c.ΔT</em>
∴ (- 1200 J) = (20.0 g)(4.186 J/g.°C)(final T - 95.0°C ).
(- 1200 J) = 83.72 final T - 7953.
∴ final T = (- 1200 J + 7953)/83.72 = 80.67 °C ≅ 81.0 °C.
<em>So, the right choice is: C. 81 degrees Celsius
</em>
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