Download App

Model Paper 9 — Chemistry STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceChemistryModel Paper 95 Marks
Question
Attempt any five of the following:
1. Why are Alkenes called olefins?
2. Convert 1-bromopropane to 2-bromopropane.
3. If Qc < Kc, when we continuously remove the product, what would be the direction of the reaction?
4. Convert methane into ethane.
5. What are cycloalkanes?
6. Write IUPAC name of following:
Image
7. How will you convert ethanoic acid into ethene?
✓

Answer

1. Alkenes are commonly known as olefins because the lower members form oily products on treatment with chlorine or bromine.
2. We can convert 1-Bromopropne into 2-Bromopropane in two steps. In the first step, the dehydrohalogenation of 1-bromo propane with alcoholic KOH gives propene which on reacting with HBr gives 2-bromo propane due to Markovnikov's rule for addition.
Image
3. Continuous removal of a product maintains Qc at a value less than Kc and reaction continues to move in the forward direction.
4. Conversion of methane into ethane:
Image
5. Cycloalkanes: When carbon atoms form a closed chain or ring structures, they are known as cycloalkanes.
Example: Cyclohexane
Image
6.
Image
7. 
Image

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "5 Marks Questions" from Model Paper 9→Model Paper 9 — all question types→Chemistry STD 11 Science question papers→Gujarat Board STD 11 Science question papers→Gujarat Board question paper generator→

Similar questions

Account for the following:
i. Ozone layer is necessary for life.
ii. The temperature of thermosphere is $1500^{\circ} \mathrm{C}$ but a person would not feel warm in it.
iii. Increased $\mathrm{SO}_2$ concentration causes chlorosis.
iv. $\mathrm{CO}_2$ keeps the earth warm.
v. The pH of normal rain water is 5.6 .
→
What will be the pressure exerted by a mixture of $3.2g$ of methane and $4.4g$ of carbon dioxide contained in a $9dm^3$ flask at $27^\circ C$?
→
Pay load is defined as the difference between the mass of displaced air and the mass of the balloon. Calculate the pay load when a balloon of radius $10 \ m$ , mass $100 \ kg$ is filled with helium at 1.66 bar at $27^{\circ} C$. (Density of air $=1.2 kg$ $m ^{-3}$ and $R =0.083 bar dm ^3 K^{-1} mol^{-1}$ ).
→
Addition of HBr to propene yields 2-bromopropane, while in the presence of benzoyl peroxide, the same reaction yields 1-bromopropane. Explain and give mechanism.
→
What are electron deficient compounds? Are $\mathrm{BCl}_3$ and $\mathrm{SiCl}_4$ electron deficient species? Explain.
→
Give one method for industrial preparation and one for laboratory preparation of $CO$ and $CO_2$ each.
→
Aluminium trifluoride is insoluble in anhydrous HF but dissolves on addition of NaF. Aluminium trifluoride precipitates out of the resulting solution when gaseous $BF_3$ is bubbled through. Give reasons.
→
What is the equilibrium concentration of each of the substances in the equilibrium when the initial concentration of ICl was 0.78M?
$2\text{ICI (g)}\rightleftharpoons\text{I}_2\text{ (g) + Cl}_2\text{ (g)};\text{ K}_{\text{c}}=0.14$
→
What will be the pressure of the gaseous mixture when 0.5 L of $\mathrm{H}_2$ at 0.8 bar and 2.0 L of dioxygen at 0.7 bar are introduced in a 1 L vessel at $27^{\circ} \mathrm{C}$ ?
→
Write a relation between $\triangle G$ and Q and define the meaning of each term and answer the following:
a. Why a reaction proceeds forward when $Q < K$ and no net reaction occurs when $Q = K$.
b. Explain the effect of an increase in pressure in terms of reaction quotient Q for the reaction:
$
CO(g)+3 H_2(g) \rightleftharpoons CH_4(g)+H_2 O(g)
$
→