Question map
Not attempted Correct Incorrect ★ Bookmarked
Loading…
Q93 (CDS-I/2004) Science & Technology › Basic Science (Physics, Chemistry, Biology) › Applied everyday chemistry Answer Verified

Rusting of Iron is due of formation of

Result
Your answer: —  Â·  Correct: C
Explanation

Rusting of iron is a chemical process that occurs when iron is exposed to moist air for a prolonged period [c4]. The process involves an oxidation reaction where iron reacts with oxygen and water to form a brown, flaky substance [c1][c3]. Chemically, rust is primarily composed of hydrated ferric oxide, represented by the formula Fe2O3·nH2O [t1][t5]. While the initial stages of corrosion may involve the formation of ferrous ions (Fe2+) and iron(II) hydroxide, these are further oxidized in the presence of oxygen to the ferric state (Fe3+) [t2][t9]. The final stable product that characterizes the brown deposit known as rust is the hydrated form of iron(III) oxide, also known as ferric oxide [t5][t6]. Therefore, hydrated ferric oxide is the most accurate description of rust's chemical composition.

Sources

  1. [1] Science-Class VII . NCERT(Revised ed 2025) > Chapter 5: Changes Around Us: Physical and Chemical > 5.3.1 Rusting > p. 62
  2. [2] Science-Class VII . NCERT(Revised ed 2025) > Chapter 4: The World of Metals and Non-metals > Activity 4.5: Let us experiment > p. 50
  3. [3] Science , class X (NCERT 2025 ed.) > Chapter 3: Metals and Non-metals > 3.5 CORROSION > p. 53
How others answered
Each bar shows the % of students who chose that option. Green bar = correct answer, blue outline = your choice.
Community Performance
Out of everyone who attempted this question.
50%
got it right
✓ Thank you! We'll review this.

SIMILAR QUESTIONS

IAS · 1994 · Q127 Relevance score: 2.02

Galvanised iron sheets are protected from rusting due to the presence of a layer of

CDS-I · 2009 · Q62 Relevance score: 0.75

The rusting of iron nail

NDA-I · 2008 · Q36 Relevance score: 0.67

When iron is left exposed in open air, it gets rested. Which costituent (s) of air is/ are responsible for rusting iron? 1. Oxygen gas present in air 2. Moisture present in air 3. Carbon dioxide gas present in air Select the correct answer using the code given below :

NDA-I · 2010 · Q96 Relevance score: 0.06

Which of the following represent a chemical change? 1. Magnetization of iron 2. Condensation of liquid 3. Burning of fuel 4. Rusting of iron Select the correct answer using the code given below : Code :

CDS-I · 2014 · Q87 Relevance score: -0.27

Iron sheet kept in moist air gets covered with rust. Rust is