Its J.J Thomson i took the test
Answer:
66.7s
Explanation:
Let's bring out the parameters we were given...
Half life = ?
Initial Concentration = 0.0576 M
Final Concentration = 0.0249 M
Time for the concentration change to occur = 97.8s - 17.1s = 80.7s
Formular for half life (t1/2) is given as;
t1/2 = ln2 / k ≈ 0.693 / k
where k = rate constant
From the formular of first order reactions;
ln[A] = ln[A]o − kt
where [A] = Final Concentration and [A]o = Initial Concentration
Inserting the values, we have;
ln(0.0249) = ln(0.0576) - k(80.7)
Upon solving for k, we have;
-0.8387 = -k(80.7)
k = 0.01039 s−1
t1/2 = 0.693 / k = 0.693 / 0.01039 = 66.7s
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Mendeleev's periodic table became widely accepted because it correctly predicted the properties of elements that had not yet been discovered.
Answer:
magnesium metal
Explanation:
According to the redox reaction equation, six electrons were transferred hence n=6 and F= Faraday's constant 96500C. ∆G° is given hence E°cell can easily be calculated as follows:
From ∆G°= -nFE°cell
E°cell= -∆G°/nF= -(-411×10^3/96500×6)
E°cell= 0.7098V
But for Al3+(aq)/Al(s) half cell, E°= -1.66V from standard table of reduction potentials.
E°cell= E°cathode- E°anode but Al3+(aq)/Al(s) half cell is the cathode
Hence
E°anode=E°cathode - E°cell
E°anode= -1.66-0.7098= -2.37V
This is the reduction potential of Mg hence the anode material was magnesium metal
