Answer:
Thus, random error primarily affects precision. Typically, random error affects the last significant digit of a measurement. The main reasons for random error are limitations of instruments, environmental factors, and slight variations in procedure.
Explanation:
Answer:
136.63 °C
Explanation:
ΔTb=Tb solution - Tb pure
Where; Tb pure = 133.60°C
molar mass of solute = 121.14 g/mol
number of moles of solute; 52.2g/121.14 g/mol = 0.431 moles
molality = 0.431 moles/350 * 10^-3 = 1.23 molal
Then;
ΔTb = Kb * m * i
Kb = 2.46°C kg mol^-1
m = 1.23 molal
i = 1
ΔTb = 2.46 * 1.23 * 1
ΔTb = 3.03 °C
Hence;
Tb solution = ΔTb + Tb pure
Tb solution = 3.03 °C + 133.60°C
Tb solution = 136.63 °C
Answer : The time it take to plate out will be, 3.69 minutes.
Explanation :
First we have to calculate the moles of Cr.

Molar mass of Cr = 51.9 g/mol

The cathode half-reaction is,

From this we conclude that,
The number of electrons (n) in the reaction are 3.
The quantity of charge required for the reduction of 1 mole of
= 
The quantity of charge required for the reduction of 0.0423 mole of
= 
Now we have to calculate the time taken.
We know that,


Thus, the time it take to plate out will be, 3.69 minutes.