Steel is an alloy containing iron - Edexcel - GCSE Chemistry - Question 4 - 2023 - Paper 1
Question 4
Steel is an alloy containing iron.
When exposed to damp air, some steels will corrode to form rust.
(a) (i) Which gas in the air is needed for corrosion to occur?
... show full transcript
Worked Solution & Example Answer:Steel is an alloy containing iron - Edexcel - GCSE Chemistry - Question 4 - 2023 - Paper 1
Step 1
Which gas in the air is needed for corrosion to occur?
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The gas necessary for corrosion to occur is D. oxygen. Oxygen is essential in the rusting process as it reacts with iron in the presence of water to form iron oxides, commonly known as rust.
Step 2
What type of reaction happens when the iron in steel corrodes?
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The type of reaction that occurs when iron in steel corrodes is C. the iron has been oxidised. During corrosion, iron loses electrons to oxygen, undergoing oxidation.
Step 3
Calculate the relative formula mass of this iron chloride.
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
To calculate the relative formula mass of iron chloride (FeCl₃), we add the atomic masses of its constituent elements:
[\text{Relative formula mass} = \text{mass of Fe} + 3 \times \text{mass of Cl}]
