AP EAMCET201920 Apr 2019Morning ShiftChemistrySurface ChemistryActual
Noble metals, like gold and platinum are soluble in which of the following mixtures?
Options
- A(1: 1 ) mixture of conc. ( HNO ₃ ) and conc. ( H ₂ SO ₄ )
- B(1: 3 ) mixture of conc. ( HCl ) and conc. ( HNO ₃ )
- C(1: 3 ) mixture of conc. ( HNO ₃ ) and conc. ( HCl )
- D(1: 3 ) mixture of conc. ( H ₂ SO ₄ ) and conc. ( HCl )
Correct answer
C. (1: 3 ) mixture of conc. ( HNO ₃ ) and conc. ( HCl )
Step-by-step solution
Nobel metal such as gold and platinum are soluble in aqua-regia which is a mixture of nitric acid and hydrochloric acid in molar ratio of (1: 3 ). i.e. (3 HCl +1 HNO ₃= ) aqua-regia Hence, option (3) is correct.