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
Top Questions on Alcohols
- Molecular formula of butanol-2 is
- Write the mechanism of dehydration of ethyl alcohol with conc. H$_2$SO$_4$ at 413 K.
- Give a simple chemical test to distinguish between 3-pentanol and 2-pentanol.
Alcohols undergo a number of reactions involving the cleavage of C – OH bond. However, phenols do not undergo reactions involving the cleavage of C – OH bond. Alcohols are weaker acids than water. Alcohols react with halogen acids to form the corresponding haloaklanes. Phenols are stronger acids than alcohols. A charac- teristic feature of phenols is that they undergo electrophilic substitution reactions such as halogenation, nitration, etc. Since –OH group is a strong activating group, phenol gives trisubstituted products during halogenation, nitration, etc.
- Which of the following is a primary alcohol?
Questions Asked in JEE Main exam
In the first configuration (1) as shown in the figure, four identical charges \( q_0 \) are kept at the corners A, B, C and D of square of side length \( a \). In the second configuration (2), the same charges are shifted to mid points C, E, H, and F of the square. If \( K = \frac{1}{4\pi \epsilon_0} \), the difference between the potential energies of configuration (2) and (1) is given by:
- JEE Main - 2025
- Electromagnetic Field (EMF)
Given below are two statements:
Statement I:
will undergo alkaline hydrolysis at a faster rate than 
Statement II:
In
intramolecular substitution takes place first by involving lone pair of electrons on nitrogen.
- JEE Main - 2025
- Organic Chemistry
The effect of temperature on the spontaneity of reactions are represented as: Which of the following is correct?
- JEE Main - 2025
- Thermodynamics and Work Done
- Let \( \vec{a} = \hat{i} + 2\hat{j} + \hat{k} \) and \( \vec{b} = 2\hat{i} + 7\hat{j} + 3\hat{k} \). Let \( L_1 : \vec{r} = (-\hat{i} + 2\hat{j} + \hat{k}) + \lambda \vec{a}, \lambda \in {R} \) and \( L_2 : \vec{r} = (\hat{j} + \hat{k}) + \mu \vec{b}, \mu \in \mathbb{R} \) be two lines. If the line \( L_3 \) passes through the point of intersection of \( L_1 \) and \( L_2 \), and is parallel to \( \vec{a} + \vec{b} \), then \( L_3 \) passes through the point:
- JEE Main - 2025
- Vectors
If all the words with or without meaning made using all the letters of the word "KANPUR" are arranged as in a dictionary, then the word at 440th position in this arrangement is:
- JEE Main - 2025
- permutations and combinations
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.