All Exams Test series for 1 year @ ₹349 only
Question

In a laboratory, copper sulphate solution reacts with iron filings, causing a colour change and the deposition of a new metal. Which statement correctly explains the reason for this reaction?

This question was previously asked in
RRB NTPC 2025 Graduate CBT 2 Question Paper PDF (10-Jul-2026) (Shift 1)
The correct answer is

Iron is more reactive than copper

When iron filings are added to copper sulphate solution, iron displaces copper from the solution, forming iron sulphate and depositing reddish-brown copper metal, while the blue colour of the solution fades.

This is a displacement reaction, which occurs only when the reacting metal (iron) is more reactive than the metal in the compound (copper), as per the reactivity series.

Iron and copper do not belong to the same group in the periodic table, and their differing reactivity (not similarity) is exactly what drives this reaction, ruling out those options.

Hence, the reaction occurs because iron is more reactive than copper.

Was this answer helpful?

Similar Questions

  1. What is oxidization?
  2. With which substance does silver react and turn black?
  3. Which of the following determines that a chemical reaction has not taken place?
  4. Which chemical process results in the formation of plaque on copper, the rusting of iron and the blackening of silver?
  5. During an experiment, iron nails are placed in copper sulphate solution, and a reddish-brown deposit forms on the nails. What does this observation demonstrate about the type of chemical reaction and the substances involved?

  6. In the reaction Na2SO4(aq) + BaCl2(aq) → BaSO4(*) + 2NaCl(aq), what will be the actual physical state that can replace (*)?

  7. A student mixes aqueous solutions of barium chloride and sodium sulphate. A white curd-like substance forms instantly. What type of chemical reaction is primarily responsible for this observation?

  8. ________ is not a chemical change.
  9. Which of the following solutions has the highest concentration of hydrogen ions?
  10. Which of the following product is formed due to burning of a magnesium ribbon with a spirit lamp?

Important Questions from Chemical Reaction

  1. Which of the following statement is/are true?

    I. In physical change new substance is formed. substance is formed.

    II. In chemical change no new substance is formed.

  2. Which of the following cells involves similar chemical reactions?

  3. The information not obtained from balanced chemical equation is

  4. Oxygen cannot be obtained by which one of the following methods?

  5. Which of the following statement is correct?

    I. Insoluble salt is obtained by precipitation reaction.

    II. Addition of oxygen or loss of hydrogen is called oxidation.

Need Expert Advice?
Upcoming Exams
RRB JE
October 27, 2026
RRB ALP
November 03, 2026
Test Series
RRB NTPC img
Railways
RRB NTPC Under Graduate 2026 New Mock Test Series
1612 Tests 1 Tests Free
678 Attempts
4.3(510)
English, Hindi, Telugu +7 More
More Questions from RRB NTPC

Start Your Preparation with Prepp Mobile App

Download the app from Google Play & App Store
Download the app from Google Play & App Store
Prepp Mobile App