Questions

case /data -based [Che-4M]

🎯

Test yourself on this topic

2 questions · timed · auto-graded

Question 14 Marks
Carbon compounds can be easily oxidised on combustion. In addition to this complete oxidation, we have reactions in which alcohols are converted to carboxylic acids. We see that some substances are capable of adding oxygen to others. These substances are known as oxidising agents. Also some compounds are capable of adding hydrogen. These substances are known as reducing agents.
i. Give any two examples of good oxidising agent.
ii. Complete the reaction:
$\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{OH}+\text { Alk. } \mathrm{KMnO}_{4} \rightarrow$
iii. Give some uses of Alcohol.
OR
Why Acidified potassium dichromate is called an oxidising agent?
Answer
i. Alkaline potassium permanganate or acidified potassium dichromate are examples of good oxidising agents.
ii. $\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{OH}+\mathrm{Alk} . \mathrm{KMnO}_{4} \rightarrow \mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{COOH}$
iii. Alcohol is used as a solvent, spirit, alcoholic drinks, fuels, etc
OR
Acidified potassium permagnet $\mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}$ is a good oxidising agent because it can add oxygen to the reactant molecule very easily and convert them to acid.
View full question & answer
Question 24 Marks
A hydrocarbon (P) has the molecular formula $\mathrm{C}_{10} \mathrm{H}_{22}$. A hydrocarbon (Q) has two carbon atoms less than (P) and belong to the same homologous series. A hydrocarbon (R) has two carbon atoms more than (P) and belong to the same homologous series.
i. What is the molecular formula of (Q)? Also write its IUPAC name.
ii. To which homologous series do the compound $(\mathrm{P}),(\mathrm{Q})$ and $(\mathrm{R})$ belong?
iii. State two characteristics of homologous series?
OR
What can you say about properties of compounds (P), (Q) and (R)
Answer
i. Molecular formula of (Q) is $\mathrm{C}_{8} \mathrm{H}_{18}$ as it has two carbon atoms less than (P). Its IUPAC name is octane
ii. Compounds (P), (Q) and (R) are alkanes having general formula $\mathrm{C}_{n} \mathrm{H}_{2 n+2}$. alkanes are the compounds having single bond between carbon atoms
iii. a. All the members of the homologous series can be represented by the same general formula.
b. Any two adjacent homologues differ by 1 carbon atom and 2 hydrogen atoms in their molecular formulae.
OR
They have same chemical properties.
Compound $(\mathrm{P}),(\mathrm{Q})$ and $(\mathrm{R})$ belong to same homologous series so they have different physical properties but similar chemical properties. They have same general formula $\mathrm{C}_{\mathrm{n}} \mathrm{H}_{2 \mathrm{n}+2}$. They differ by 2 carbon atoms and 4 hydrogen atoms.
View full question & answer
case /data -based [Che-4M] - Science STD 10 Questions - Vidyadip