Answer: option A.
A physical change occurred in which the iron remained iron, but lost one of its physical properties
Explanation: magnetization and demagnetization is a physical change as no new substance is form and it is easily reversed. When an iron rod is magnetized, it can loss it magnetic property by hitting it. So when an iron rod which is magnetized falls from a height it can also loss its magnetic property
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Answer:</h3>
Balanced equation: 4Fe + 3O₂ → 2Fe₂O₃
Moles of oxygen gas = 9 moles
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Explanation:</h3>
To answer the question;
- We first write the balanced equation between iron metal and Oxygen
- The balanced equation is given as;
4Fe + 3O₂ → 2Fe₂O₃
- We are given 6 moles of Fe₂O₃
We are required to determine the number of moles of oxygen needed to form 6 moles of Fe₂O₃.
- From the equation, 3 moles of oxygen gas reacts to produce 2 moles of Fe₂O₃
- This means, the mole ratio of O₂ to Fe₂O₃ is 3 : 2
Therefore; Moles of O₂ = Moles of Fe₂O₃ × 3/2
Hence, moles of oxygen = 6 moles × 3/2
= 9 moles
Thus, Moles of Oxygen needed is 9 moles
It is a physical change because only the states as being changes, not the actual bonds in the compound.
