Class 12 Extra questions English Flamingo Chapter 3 Deep Water by William Douglas

Class 12 Extra questions                    English Flamingo Chapter 3                                                                           Deep Water by William Douglas 1. Q: What initial event led to Douglas's fear of water?    A: Douglas's fear of water began when he was thrown into the deep end of the Y.M.C.A. pool by a bully, nearly causing him to drown.   2. Q: How did Douglas’s early experiences at the beach contribute to his fear?    A: As a child, Douglas had been knocked down by waves at a beach in California, which left him frightened of water. 3. Q: Why did Douglas decide to learn swimming despite his fear?    A: Douglas decided to learn swimming to overcome his debilitating fear and regain confidenc...

"Study With Mayank Sir" Chemistry MCQ Chapter 3 chemical kinetics

"Study With Mayank Sir" - To hit the ball out of the boundary line

WA - 8290535520

Youtube - https://www.youtube.com/@dasklibro

Chapter–3 : Chemical Kinetics (रासायनिक गतिकी)

Question Type: MCQ (Knowledge Based)
Marks per Question: 0.5


Q1.

Chemical kinetics deals with —
रासायनिक गतिकी संबंधित है —
A) Energy of reaction / अभिक्रिया की ऊर्जा
B) Rate of reaction / अभिक्रिया की दर ✅
C) Equilibrium constant / साम्यांक
D) Structure of atom / परमाणु संरचना

Answer: B
Explanation: Chemical kinetics studies the rate and mechanism of reactions.


Q2.

Rate of reaction is defined as —
अभिक्रिया की दर परिभाषित की जाती है —
A) Change in temperature per unit time
B) Change in concentration per unit time / प्रति इकाई समय सांद्रता में परिवर्तन ✅
C) Energy released per unit time
D) Volume change per unit time

Answer: B
Explanation: Rate = change in concentration of reactant or product per unit time.


Q3.

Unit of rate of reaction is —
अभिक्रिया की दर की इकाई है —
A) mol L⁻¹
B) s⁻¹
C) mol L⁻¹ s⁻¹ / मोल ली⁻¹ सेकंड⁻¹ ✅
D) L mol⁻¹ s⁻¹

Answer: C
Explanation: Rate = concentration/time.


Q4.

Average rate of reaction is calculated over —
औसत अभिक्रिया दर निकाली जाती है —
A) Instant
B) Very small time
C) Finite time interval / सीमित समय अंतराल ✅
D) Zero time

Answer: C
Explanation: Average rate is measured over a finite interval.


Q5.

Instantaneous rate is equal to —
तत्क्षणिक दर बराबर होती है —
A) Average rate
B) Slope of tangent / स्पर्श रेखा का ढाल ✅
C) Area under curve
D) Intercept

Answer: B
Explanation: Instantaneous rate = slope of tangent to concentration–time graph.


Q6.

Rate law expresses relation between —
दर नियम संबंध बताता है —
A) Rate and temperature
B) Rate and concentration / दर व सांद्रता ✅
C) Rate and pressure
D) Rate and volume

Answer: B
Explanation: Rate law relates rate with concentration of reactants.


Q7.

Rate law is determined by —
दर नियम निर्धारित होता है —
A) Balanced equation
B) Stoichiometry
C) Experiment / प्रयोग द्वारा ✅
D) Molecular mass

Answer: C
Explanation: Rate law is experimentally determined.


Q8.

Order of reaction is —
अभिक्रिया का क्रम होता है —
A) Sum of stoichiometric coefficients
B) Sum of powers of concentration terms / सांद्रता के घातों का योग ✅
C) Molecularity
D) Temperature dependent

Answer: B
Explanation: Order = sum of exponents in rate law.


Q9.

Order of reaction may be —
अभिक्रिया का क्रम हो सकता है —
A) Zero / शून्य ✅
B) Fractional / भिन्नात्मक ✅
C) Integer / पूर्णांक ✅
D) All of these / ये सभी ✅

Answer: D
Explanation: Order can be zero, fractional, or integer.


Q10.

Molecularity of reaction is —
अभिक्रिया की अणुकता होती है —
A) Experimental
B) Theoretical / सैद्धांतिक ✅
C) Fractional
D) Zero

Answer: B
Explanation: Molecularity is based on reaction mechanism.


Q11.

Molecularity can never be —
अणुकता कभी नहीं हो सकती —
A) One
B) Two
C) Three
D) Fractional / भिन्नात्मक ✅

Answer: D
Explanation: Molecularity is always a whole number.


Q12.

Rate constant depends on —
दर स्थिरांक निर्भर करता है —
A) Concentration
B) Temperature / तापमान ✅
C) Pressure only
D) Time

Answer: B
Explanation: Rate constant varies with temperature.


Q13.

Unit of rate constant for first order reaction is —
प्रथम क्रम अभिक्रिया के लिए दर स्थिरांक की इकाई —
A) mol L⁻¹ s⁻¹
B) L mol⁻¹ s⁻¹
C) s⁻¹ / सेकंड⁻¹ ✅
D) mol² L⁻² s⁻¹

Answer: C
Explanation: For first order, unit = s⁻¹.


Q14.

Half-life of first order reaction depends on —
प्रथम क्रम अभिक्रिया का अर्ध-आयु निर्भर करता है —
A) Initial concentration
B) Rate constant / दर स्थिरांक ✅
C) Time
D) Temperature only

Answer: B
Explanation: ( t_{1/2} = 0.693/k )


Q15.

Half-life of first order reaction is —
प्रथम क्रम अभिक्रिया का अर्ध-आयु होता है —
A) Constant / स्थिर ✅
B) Variable
C) Zero
D) Infinite

Answer: A
Explanation: Independent of initial concentration.


Q16.

Zero order reaction rate is independent of —
शून्य क्रम अभिक्रिया की दर निर्भर नहीं करती —
A) Temperature
B) Catalyst
C) Concentration / सांद्रता ✅
D) Time

Answer: C
Explanation: Rate = k for zero order reaction.


Q17.

Unit of rate constant for zero order reaction is —
शून्य क्रम अभिक्रिया में दर स्थिरांक की इकाई —
A) s⁻¹
B) mol L⁻¹ s⁻¹ / मोल ली⁻¹ सेकंड⁻¹ ✅
C) L mol⁻¹ s⁻¹
D) mol² L⁻² s⁻¹

Answer: B


Q18.

Order and molecularity are equal for —
क्रम व अणुकता समान होती है —
A) Complex reactions
B) Elementary reactions / प्राथमिक अभिक्रिया ✅
C) Reversible reactions
D) Chain reactions

Answer: B


Q19.

Activation energy is minimum for —
सक्रियण ऊर्जा न्यूनतम होती है —
A) Uncatalysed reaction
B) Catalysed reaction / उत्प्रेरित अभिक्रिया ✅
C) Endothermic reaction
D) Slow reaction

Answer: B


Q20.

Arrhenius equation relates —
एरहेनियस समीकरण संबंध बताता है —
A) Rate and concentration
B) Rate constant and temperature / दर स्थिरांक व तापमान ✅
C) Pressure and volume
D) Energy and mass

Answer: B


Q21.

Arrhenius equation is —
एरहेनियस समीकरण है —
A) k = Ae⁻ᴱᵃ⁄ᴿᵀ ✅
B) PV = nRT
C) ΔG = ΔH − TΔS
D) E = mc²

Answer: A


Q22.

Activation energy is defined as —
सक्रियण ऊर्जा की परिभाषा —
A) Energy of reactants
B) Energy of products
C) Minimum energy required for reaction / न्यूनतम आवश्यक ऊर्जा ✅
D) Heat evolved

Answer: C


Q23.

Catalyst works by —
उत्प्रेरक कार्य करता है —
A) Increasing temperature
B) Increasing concentration
C) Lowering activation energy / सक्रियण ऊर्जा घटाकर ✅
D) Changing ΔG

Answer: C


Q24.

Pseudo-first order reaction appears as —
छद्म प्रथम क्रम अभिक्रिया प्रतीत होती है —
A) Zero order
B) First order / प्रथम क्रम ✅
C) Second order
D) Third order

Answer: B


Q25.

Example of pseudo-first order reaction —
छद्म प्रथम क्रम अभिक्रिया का उदाहरण —
A) Hydrolysis of ester / एस्टर का जल अपघटन ✅
B) Combustion
C) Neutralisation
D) Photosynthesis

Answer: A


Q26.

Collision theory applies to —
संघटन सिद्धांत लागू होता है —
A) Solids
B) Liquids
C) Gases / गैसें ✅
D) Colloids

Answer: C
Explanation: Collision theory is mainly applicable to gaseous reactions.


Q27.

Effective collision requires —
प्रभावी टक्कर के लिए आवश्यक है —
A) High pressure only
B) Proper orientation and energy / उचित अभिविन्यास व ऊर्जा ✅
C) Large volume
D) Catalyst only

Answer: B
Explanation: Only collisions with sufficient energy and proper orientation are effective.


Q28.

Rate of reaction increases with temperature because —
तापमान बढ़ाने पर अभिक्रिया की दर बढ़ती है क्योंकि —
A) Volume increases
B) Activation energy increases
C) Number of effective collisions increases / प्रभावी टक्करों की संख्या बढ़ती है ✅
D) Concentration decreases

Answer: C


Q29.

Frequency factor represents —
आवृत्ति गुणांक दर्शाता है —
A) Energy of collision
B) Number of collisions per second / प्रति सेकंड टक्करों की संख्या ✅
C) Activation energy
D) Heat of reaction

Answer: B


Q30.

Slope of Arrhenius plot gives —
एरहेनियस आलेख का ढाल देता है —
A) R
B) −Ea/R / −सक्रियण ऊर्जा/गैस स्थिरांक ✅
C) A
D) k

Answer: B


Q31.

First order reaction graph between log(a−x) vs t is —
प्रथम क्रम अभिक्रिया में log(a−x) व t का आलेख —
A) Curve
B) Straight line / सीधी रेखा ✅
C) Parabola
D) Hyperbola

Answer: B


Q32.

Rate constant for a given reaction —
किसी अभिक्रिया के लिए दर स्थिरांक —
A) Changes with time
B) Remains constant at fixed temperature / नियत ताप पर स्थिर रहता है ✅
C) Depends on concentration
D) Depends on volume

Answer: B


Q33.

Slowest step of reaction determines —
अभिक्रिया का सबसे धीमा चरण निर्धारित करता है —
A) Order
B) Rate / दर ✅
C) Molecularity
D) Energy

Answer: B


Q34.

Integrated rate equation is used to determine —
समाकलित दर समीकरण उपयोग होता है —
A) Order of reaction / अभिक्रिया का क्रम ✅
B) Temperature
C) Pressure
D) Volume

Answer: A


Q35.

Unit of rate constant depends on —
दर स्थिरांक की इकाई निर्भर करती है —
A) Temperature
B) Order of reaction / अभिक्रिया का क्रम ✅
C) Catalyst
D) Time

Answer: B


Q36.

Rate law expression for zero order reaction is —
शून्य क्रम अभिक्रिया का दर नियम —
A) Rate = k[A]
B) Rate = k[A]²
C) Rate = k / दर = k ✅
D) Rate = k[A][B]

Answer: C


Q37.

In first order reaction, plot of ln k vs 1/T is —
प्रथम क्रम अभिक्रिया में ln k व 1/T का आलेख —
A) Curved
B) Straight line / सीधी रेखा ✅
C) Zig-zag
D) Random

Answer: B


Q38.

Temperature coefficient is defined as —
ताप गुणांक परिभाषित है —
A) Ratio of rate constants at two temperatures / दो तापों पर दर स्थिरांक का अनुपात ✅
B) Difference of rates
C) Energy change
D) Volume ratio

Answer: A


Q39.

If temperature increases by 10°C, reaction rate generally —
यदि ताप 10°C बढ़े तो अभिक्रिया की दर सामान्यतः —
A) Remains same
B) Doubles / दोगुनी हो जाती है ✅
C) Becomes zero
D) Decreases

Answer: B


Q40.

Activation energy is denoted by —
सक्रियण ऊर्जा को दर्शाया जाता है —
A) ΔH
B) Ea / Eₐ ✅
C) k
D) R

Answer: B


Q41.

Rate determining step is —
दर निर्धारक चरण होता है —
A) Fastest step
B) Slowest step / सबसे धीमा चरण ✅
C) Last step
D) Reversible step

Answer: B


Q42.

Which factor does NOT affect rate of reaction?
कौन-सा कारक अभिक्रिया की दर को प्रभावित नहीं करता —
A) Concentration
B) Temperature
C) Catalyst
D) Colour of reactants / अभिकारकों का रंग ✅

Answer: D


Q43.

First order reactions have constant —
प्रथम क्रम अभिक्रियाओं में स्थिर रहता है —
A) Rate
B) Half-life / अर्ध-आयु ✅
C) Concentration
D) Volume

Answer: B


Q44.

Graph of concentration vs time for zero order is —
शून्य क्रम में सांद्रता बनाम समय का आलेख —
A) Straight line / सीधी रेखा ✅
B) Curve
C) Parabola
D) Hyperbola

Answer: A


Q45.

Reaction order can be fractional because —
अभिक्रिया का क्रम भिन्नात्मक हो सकता है क्योंकि —
A) Molecularity is fractional
B) Complex mechanism / जटिल अभिक्रिया यंत्रणा ✅
C) Temperature effect
D) Pressure effect

Answer: B


Q46.

Rate constant increases exponentially with —
दर स्थिरांक घातीय रूप से बढ़ता है —
A) Pressure
B) Concentration
C) Temperature / तापमान ✅
D) Volume

Answer: C


Q47.

Activation energy graph is plotted between —
सक्रियण ऊर्जा का आलेख बनाया जाता है —
A) Rate vs time
B) Energy vs reaction coordinate / ऊर्जा बनाम अभिक्रिया निर्देशांक ✅
C) Concentration vs time
D) Pressure vs volume

Answer: B


Q48.

For catalysed reaction, energy profile shows —
उत्प्रेरित अभिक्रिया में ऊर्जा आलेख दर्शाता है —
A) Higher peak
B) Same peak
C) Lower peak / कम शिखर ✅
D) No peak

Answer: C


Q49.

Rate law cannot be predicted from —
दर नियम पूर्वानुमान नहीं किया जा सकता —
A) Experiment
B) Rate data
C) Balanced equation / संतुलित समीकरण ✅
D) Graph

Answer: C


Q50.

Chemical kinetics helps to understand —
रासायनिक गतिकी समझने में सहायक है —
A) How fast reaction occurs / अभिक्रिया कितनी तेजी से होती है ✅
B) Final products only
C) Colour of compounds
D) Atomic structure

Answer: A


Comments

Popular posts from this blog

CLASS 12 HINDI COMPULSORY – HALF YEARLY EXAM 2025

test mcq -1 d and f block Hindi medium

कक्षा 12 – रसायन विज्ञान (RBSE)अर्धवार्षिक परीक्षा प्रश्नपत्र