Answer:

Explanation:
The formula for efficiency is

Data:
Useful energy = 3 J
Energy input = 30 J
Calculation:

Answer:
I think that is called oxalic acid
Explanation:
Iron (iii) chloride is obtained by vapor condensation from the reaction between chlorine gas and iron fillings.
<h3>How can iron (iii) chloride be formed from iron fillings?</h3>
Iron (ii) chloride can be formed from iron fillings in the laboratory as follows:
- Iron fillings + Cl₂ → FeCl₃
Chlorine gas is introduced into a reaction vessel containing iron fillings and the iron (iii) chloride vapor formed is obtained by condensation.
In conclusion, iron (iii) chloride is formed by the the direct combination of iron fillings and chlorine gas.
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