Answer to Question #208782 in General Chemistry for KPOPOII

Question

The Sn in a 0.4352 g mineral specimen was reduced to the +2 state and titrated with 29.77 mL of 0.01735 M K2Cr2O7. Identify:

(a) balanced redox reaction

(b) oxidizing agent

(c) reducing agent

(d) type of redox titrimetry used

(e) appropriate indicator and its type

(f) color at the end point

(g) weight percent Sn (118.71 g/mol) in the sample

Answer 1

A) balanced redox reaction–

K2Cr2O7 + 3 SnCl2 +14 HCl → 3 SnCl4 +2 CrCl3 + 2 KCl + 7 H2O

b) oxidising agent –

2 Cr + 6 e- → 2 CrIII (reduction) so, K2Cr2O7 Is An oxidising agent.

c) reducing agent –

3 SnII - 6 e- → 3 SnIV (oxidation)

SnCl2 is an Reducing agent.

d) Type of titrymetry is potassium dichromate.

e)brucine is used as a indicator in dichrometry and it is a internal indicator.

f) The colour is blue.

g) 67.3%