The cell notation of a standard galvanic (voltaic) cell containing an unknown metal Y is shown below - NSC Technical Sciences - Question 6 - 2022 - Paper 2
Question 6
The cell notation of a standard galvanic (voltaic) cell containing an unknown metal Y is shown below.
Y (s) | Y^{2+} (aq) | Cu^{2+} (aq) | Cu (s)
6.1 What do the s... show full transcript
Worked Solution & Example Answer:The cell notation of a standard galvanic (voltaic) cell containing an unknown metal Y is shown below - NSC Technical Sciences - Question 6 - 2022 - Paper 2
Step 1
What do the single vertical lines (|) in the cell notation represent?
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The single vertical lines (|) in the cell notation represent phase boundaries or the interface between different phases in the electrochemical cell. Specifically, they indicate a separation between the solid and aqueous phases.
Step 2
State TWO standard conditions for the cell.
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The concentration of the solutions is 1 mol/dm³.
The temperature is maintained at 25 °C or 298 K.
Step 3
Write down the NAME or FORMULA of the oxidising agent.
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The oxidising agent in this cell is Copper (II) ions, which can be represented as Cu^{2+}.
Step 4
Identify the polarity of:
98%
120 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
6.4.1 Anode: Negative
6.4.2 Cathode: Positive
Step 5
The initial reading on a voltmeter connected across the electrodes is 1,10 V. Use a calculation to identify metal Y.
97%
117 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
To identify metal Y, we can use the Nernst equation. Given the voltage of the cell:
Ecell=Ecathode−Eanode
Let the anode be zinc (Zn) with Eanode=−0.76V and cathode as Cu:
Using the formula:
Ecell=1.10V=0.34V−EY
This leads us to:
EY=0.34V−1.10V=−0.76V
By comparing with standard electrode potentials, metal Y is identified as Zinc (Zn).
