Yokka Stars

141. Solving a chemistry problem

141. Solving a chemistry problem

Seller: Derkach

Price: 1.19 USD

Available. The final price depends on the selected options and is checked before payment.

Product description

In standard solutions of a potassium salt with a concentration of c (K +), the electrode potentials of the potassium-selective electrode were measured relative to the silver chloride electrode:

C (K +), mol/L 1.0*10 ^-1 1.0*10 ^-2 1.0*10 ^-3 1.0*10 ^-4

E, mV 100 46.0 -7.00 -60.0

Based on these data, a calibration graph was constructed in the coordinates E - pc (K +).

A weighed portion of a sample weighing 0.2000 g, containing potassium, was dissolved in water and the volume was brought to V ml. Then the electrode potential of the potassium-selective electrode (Ex) was measured in the resulting solution:

Option 1

V, ml 100.0

Ek, mV 60.0

Calculate the mass fraction (%) of potassium in the sample.

Additional information

If you do not open the file - install the RAR archiver. Inside the archive you will find a solution in Word format.