A sample of 4.5 mg of an unknown monohydric alcohol, R–OH was added to methylmagnesium iodide. A gas is evolved and is collected and its volume measured to be 3.1 mL. The molecular weight of the unknown alcohol is___ g/mol. [Nearest integer]
Correct Answer: 33
Solution and Explanation
moles of CH4 = moles of ROH
⇒ \(\frac{V^2}{2400}\)=\(\frac{m}{M.M}\) (Assuming NTP Condition )
⇒\(\frac{3.1}{22400}\)=\(\frac{4.5×10^{−3}}{M⋅M}\)
⇒MM=32.51
Nearest Integer = 33
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Concepts Used:
Alcohols
What is Alcohol?
Alcohol is a derivative of water (H2O) that has one, two, or more hydroxyl groups that are attached to a carbon atom of a hydrocarbon chain (an alkyl group). It is one of the most common organic compounds used in sweeteners, fragrances, and medicine.
Read More: Types of Alcohol
Uses of Alcohol:
- Ethanol is the alcohol used in alcoholic drinks. It can be used as an industrial methylated spirit where methanol is used very little in quantity as it can be dangerous.
- It is used as fuel to produce carbon dioxide and water by the process of fermentation. Whereas methanol burns carbon dioxide and water to facilitate combustion.
- Alcohol is an organic compound used as a solvent that is insoluble in water.
- It can be used to lower the level of sugar.
- Alcohol is used as a preservative in laboratories.