Advertisements
Advertisements
प्रश्न
Which of the following is used for dissolution of gold?
विकल्प
Hydrochloric acid
Sulphuric acid
Nitric acid
Aqua regia
उत्तर
Aqua regia
Explanation -
Aqua Regia is a highly corrosive mixture of conc. nitric acid and conc. hydrochloric acid in the ratio of 1:3. It can dissolve noble metals including gold.
APPEARS IN
संबंधित प्रश्न
Why do HCl, HNO3, etc., show acidic characters in aqueous solutions while solutions of compounds like alcohol and glucose do not show acidic character?
Fill in the blank in the following sentences:
Substances do not show their acidic properties without.......................... .
What is the chemical formula of washing soda?
Name the product formed when Cl2 and H2 produced during the electrolysis of brine are made to combine.
What is the chemical name of bleaching powder?
If you take some distilled water in a test-tube, add an equal amount of acetic acid to it, shake the test-tube well and leave it undisturbed on the test-tube stand, then after about 5 minutes what would you observe?
(A) There is a layer of water over the layer of acetic acid.
(B) A precipitate is setting at the bottom of the test-tube.
(C) Bubbles of colourless gas are coming out of the test-tube.
(D) There is a clear, colourless transparent solutions in the test-tube.
What happens when a solution of an acid is mixed with a solution of a base in a test tube?
- The temperature of the solution increases
- The temperature of the solution decreases
- The temperature of the solution remains the same
- Salt formation takes place
If a few drops of a concentrated acid accidentally spills over the hand of a student, what should be done?
Take a clean test tube with a holder and pour some dilute hydrochloric acid. Add a few pieces of magnesium ribbon pieces slowly. What do you observe? Now show a burning match stick near the mouth of the test tube. Do you hear any sound? The gas burns with a pop sound. From this, it is observed that hydrogen gas has been formed due to the reaction between acid and metal.
Consider the following salt:
\[\ce{ZCO3}\]
What would be the change in colour in blue litmus if \[\ce{ZCO3}\] is added to it and Z is potassium?
