Science
An iron nail is added to each of the two test tubes ‘P’ and ‘Q’ containing aqueous copper (II) sulphate and aqueous silver nitrate respectively. Which of the following observation is correct?
options
- In test tube ‘P’ iron nail is coated with a blue coating and in test tube ‘Q’ there is no reaction.
- Iron nail is coated with a brown coating in test tube ‘P’ and silver coating in test tube ‘Q’.
- There is no reaction in either of the test tubes ‘P’ or ‘Q’.
- There is no reaction in test tube ‘P’ but a silver coating on iron nail is seen in test tube ‘Q’.
Chemical Reaction
3 Likes
Answer
Iron nail is coated with a brown coating in test tube ‘P’ and silver coating in test tube ‘Q’.
Reason —
In test tube ‘P’, the solution contains copper (II) sulphate (CuSO4) so when an iron nail is dipped into it, a displacement reaction occurs because iron (Fe) is more reactive than copper (Cu).
Iron displaces copper from copper sulphate, forming iron(II) sulphate (FeSO4) and brown copper metal, which gets deposited on the nail.
Fe(s) + CuSO4(aq) → FeSO4(aq) + Cu(s)
Thus, the nail becomes coated with brown copper.
In test tube ‘Q’, the solution contains silver nitrate (AgNO3). Again, iron is more reactive than silver (Ag), so it displaces silver from the solution, forming iron(II) nitrate (Fe(NO3)2) and depositing shiny silver metal on the nail.
Fe(s) + 2AgNO3(aq) → Fe(NO3)2(aq) + 2Ag(s)
Hence, in test tube ‘P’ the nail gets a brown coating of copper and in test tube ‘Q’ a silver coating is formed.
Answered By
3 Likes
Related Questions
Which of the following equations represent redox reactions and what are the values for ‘p’ and ‘q’ in these equations?
- Equation 1 :
- Equation 2 :
options
- Only equation 1 is a redox reaction, p = 1 and q = 3
- Both equations 1 and 2 are redox reactions, p = 2 and q = 4
- Only equation 2 is a redox reaction, p = 2 and q = 10
- Both equations 1 and 2 are redox reactions, p = 2 and q = 10
Four statements about the reactions of oxides with dilute hydrochloric acid and aqueous sodium hydroxide are listed.
I. Aluminium oxide reacts with both dilute hydrochloric acid and aqueous sodium hydroxide.
II. Calcium oxide reacts with dilute hydrochloric acid and aqueous sodium hydroxide.
III. Zinc oxide reacts with both dilute hydrochloric acid and aqueous sodium hydroxide.
IV. Sulphur dioxide does not react with either dilute hydrochloric acid or aqueous sodium hydroxide.
Which statements are correct?
options
- I and II
- I and III
- II and IV
- III and IV
Methyl orange is added to dilute hydrochloric acid and to aqueous sodium hydroxide. What is the colour of the methyl orange in each solution?
Sample Colour in dilute hydrochloric acid Colour in aqueous sodium hydroxide A Orange Red B Red Yellow C Red Orange D Yellow Red options
- A
- B
- C
- D
Which of the following substances when dissolved in equal volume of water, will have the highest pH value?
options
- Sulphuric acid
- Acetic acid
- Magnesium hydroxide
- Sodium hydroxide