Please show full work, thanks Tungsten trioxide (WO3) has a rich yellow color an

Question

Please show full work, thanks

Tungsten trioxide (WO3) has a rich yellow color and is often used as a pigment in ceramics and paints. In order to test a ceramic vase for its WO3 content, a 10.04 g sample of the vase was ground and reduced with Pb(Hg) to convert any WOs to W* The resulting W3 was transferred to 500.0 mL of 1.00 M HCI. A 100.00 mL aliquot of the HCI solution required 11.58 mL of 0.09640 M potassium permanganate (KMnO4) to reach the purple endpoint. A blank required 0.27 mL. Balance the reaction below and determine the percent WO3 in the ceramic sample. Number 22.37 %WO,

Explanation / Answer

Balanced equation:
5 W{3+} + 3 MnO4{-} + 24 H{+} = 5 W{6+} + 3 Mn{2+} + 12 H2O

Moles of MnO4 reacted = 11.58 x 0.0964 / 1000 =  0.001116312 Moles

Moles of W was present =  0.001116312 x 5 /3 =  0.00186052 Moles

Moles of W present in 500 ml solution =  0.00186052 x 5 =  0.0093026 Moles

Molar mass of WO3 is 231.8382 g/mol

The amount of WO3 in the flask and sample = 0.0093026 moles x 231.8382 g/mol = 2.1566 g
% WO3 in the sample = 2.1566 x 100 / 10.04 = 21.48%

Related Questions

Navigate

• Browse (All)
• Browse P
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.