The given graph shows the effect of substrate concentration on the rate of reaction of the enzyme green gram-phosphatase. What does the graph indicate?

In given graph, initial rate of enzymatic reaction increases but after sometime began to show down due to presence of an enzyme inhibitor.

The rate of enzyme reaction is directly proportional to the substrate concentration

The correct Option is "Presence of an enzyme inhibitor in the reaction mixture"

Formation of an enzyme-substrate complex

At higher substrate concentration, the pH increase

For a chemical reaction $X \to P$, the rate of reaction doubles when the concentration of X is increased 4 times. The order of reaction with respect to X is

${r_1} = k{\left[ X \right]^n}\,\,......\left( i \right)\,\,\,2{r_1} = k{\left[ {4X} \right]^n}\,\,......\left( {ii} \right)\,\,\,\,\left( {ii} \right) \div \,\left( i \right)\,\,\, \Rightarrow \frac{{2{r_1}}}{{{r_1}}} = \frac{{k{{\left[ {4X} \right]}^n}}}{{k{{\left[ X \right]}^n}}} \Rightarrow 2 = {\left( 2 \right)^{2n}} \Rightarrow n = \frac{1}{2}$

The correct Option is "$\frac{1}{2}$"

In a reaction, the rate of reactions is proportional to its active mass. This statement is known as

The rate of a reaction is proportional to its active mass this is called law of mass action.

The correct Option is "Law of mass-action"

The units of rate of reaction are

The rate of reaction is defined as the rate of disappearance of reactant per unit time or the rate of appearance of product per unit time. Lets consider a reaction A→B+C The rate of the reaction for the reaction will be; Rate=$ - \frac{{\delta A}}{{\delta T}} = \frac{{\delta B}}{{\delta T}} = \frac{{\delta C}}{{\delta T}}$ As, it is the ratio of concentration per unit time and unit of concentration is molL$^{−1}$ andunit of time is sec. The unit of rate of reaction is ${\rm{mol}}\;{{\rm{L}}^{ - 1}}\;{{\rm{s}}^{ - 1}}$

${\rm{L}}\;{\rm{mo}}{{\rm{l}}^{ - 1}}\;{{\rm{s}}^{ - 1}}$

The correct Option is "${\rm{mol}}\;{{\rm{L}}^{ - 1}}\;{{\rm{s}}^{ - 1}}$"

${\rm{mol}}\;{{\rm{s}}^{ - 1}}$

The rate of reaction increases with temperature due to

When heat energy is supplied, kinetic energy of reactant molecules increase. This will increase the number of collisions and ultimately rate of reaction will be enhanced.

The correct Option is "Increase in collision frequency"

The unit and value of rate constant and that of rate of reaction are same for

For zero order reaction, for example, $A \to B$ $\frac{{ - d\left[ A \right]}}{{dt}} = k{\left[ A \right]^0}$ $\frac{{ - d\left[ A \right]}}{{dt}} = k$

The correct Option is "Zero order"

The rate of reaction: $2{\rm{NO}} + {\rm{C}}{{\rm{l}}_2} \to 2{\rm{NOCl}}$ is given by the rate, equation $rate\; = k{\left[ {{\rm{NO}}} \right]^2}\left[ {{\rm{C}}{{\rm{l}}_2}} \right].$ The value of the rate constant can be increased by:

The correct Option is "Increasing the temperature"

Increasing the concentration of ${\rm{NO}}$

Increasing the concentration of the ${{\rm{C}}{{\rm{l}}_2}}$

If the rate of reaction $A \to B$ doubles on increasing the concentration of A by 4 times, the order of the reaction is

For the reaction $A \to B$ On increasing the concentration of reactant $\left( {i.e.,A} \right)$ by 4 times , the rate of reaction becomes double ,hence order of reaction is $\frac{1}{2}$.

The correct Option is "$\frac{1}{2}$"

Rate of endothermic reactions increase with increase in temperature while that of exothermic reactions decrease with increasing temperature.

Decreases with increase in temperature

Increases with increase in temperature

The correct Option is "May increase or decrease with increase in temperature"

Does not depends on temperature

The rate of reaction between two reactants $A$ and $B$ decreases by a factor 4, if the concentration of reactant $B$ is doubled. The order of this reaction with respect to $B$ is:

$r = K{\left[ A \right]^m}{\left[ B \right]^n};$ ${\rm{Also}},\;\;\;\frac{r}{4} = K{\left[ A \right]^m}{\left[ {2B} \right]^n}$ $4 = {\left( {\frac{1}{2}} \right)^n}\;\;{\rm{or}}\;\;{2^2} = {2^{ - n}}$ $\therefore \;\;n = - 2$

As the reaction progresses, the rate of reaction

The rate of reaction or speed of reaction for a reactant or product is defined as how fast or slow a reaction takes place. The rate of reaction decreases as the reaction proceeds because the concentration of reactants is high at the start and with time, this concentration decreases and the reaction gets slower. So, the rate of reaction is dependent on concentration and hence, decreases with the passage of time.

The correct Option is "Decreases"

First increases, then decreases

In a reaction, when the concentration of reactant is increased two times, the increase in rate of reaction was four times. Order of reaction is

For second order reaction, $\frac{{dx}}{{dt}}(rate) \propto {\left[ A \right]^2}$ ${ \because }$ Rate Of reaction increases four times when concentration of reaction is increased two times. $\therefore $ It is second order reaction.

In a chemical reaction two reactants take part. The rate of reaction is directly proportion to the concentration of one of them and inversely proportional to the concentration of the other. The order of reaction is

The order of reaction is zero. Suppose the following reaction take place . $A + B \to product$ $\therefore \;rate = \left[ A \right]{\left[ B \right]^{ - 1}}$ $\therefore \;order\;{\rm{ }} = 1 + \left( { - 1} \right) = 0$

Which of the following will have the faster rate of reaction with $B{r_2}/FeB{r_3}$

Methoxy $\left( { - OC{H_3}} \right)$ is strong electron releasing group.

For the reaction $A \to B,$ when concentration of $A$ is made 1.5 times, the rate of reaction becomes 1.837 times. The order of reaction is

$r = k{\left[ A \right]^\alpha } = k{a^\alpha }$ $1.837\;r = k{\left( {1.5a} \right)^\alpha }$ Dividing, $1.837 = {\left( {1.5} \right)^\alpha }$ $\alpha = 1.5$ Hence, order of reaction =1.5

For the reaction $A + 2B \to C$, the rate of reaction at a given instant can be given by

For the reaction, $A + 2B \to C$ Rate of reaction at a given instant can be represented by ${\rm{rate}} = - \frac{{d\left[ A \right]}}{{dt}} = - \frac{1}{2}\frac{{d\left[ B \right]}}{{dt}} = + \frac{{d\left[ C \right]}}{{dt}}$

$ + \frac{{d\left[ A \right]}}{{dt}} = + \frac{1}{2}\frac{{d\left[ B \right]}}{{dt}} = + \frac{{d\left[ C \right]}}{{dt}}$

$\frac{{d\left[ A \right]}}{{dt}} = - \frac{1}{2}\frac{{d\left[ B \right]}}{{dt}} = - \frac{{d\left[ C \right]}}{{dt}}$

The correct Option is "$ - \frac{{d\left[ A \right]}}{{dt}} = - \frac{1}{2}\frac{{d\left[ B \right]}}{{dt}} = + \frac{{d\left[ C \right]}}{{dt}}$"

$ + \frac{{d\left[ A \right]}}{{dt}} = + \frac{1}{2}\frac{{d\left[ B \right]}}{{dt}} = + \frac{{d\left[ C \right]}}{{dt}}$

For the chemical change $A \to B$ it is found that the rate of reaction doubles when the concentration is increased by 4 times. The order of the reaction is

$A \to B$ $\frac{{dx}}{{dt}} = k{\left[ A \right]^n}$ $\frac{{dx'}}{{dt}} = k{\left[ {4A} \right]^n}$ $\frac{{dx'/dt}}{{dx/dt}} = {\left( {\frac{4}{1}} \right)^n}$ $2 = {\left( {\frac{4}{1}} \right)^n}$ $n = \frac{1}{2}$

The reason for almost doubling the rate of reaction on increasing the temperature of the reaction system by $10^\circ C$ is

On increasing the temperature the kinetic energy of the reacting molecules increases and hence, number of collisions increases. So, the rate of reaction will also be increased.

The value of threshold energy increases

The correct Option is "Collision frequency increases"

The fraction of the molecules having energy equal to threshold energy increases

If the rate of reaction between $A$ and $B$ is given by, $rate = K\left[ A \right]{\left[ B \right]^n},$ then the reaction is:

Order of reaction is sum of powers raised on concentration terms in order to write rate expression.

Overall order is $\left( {1 + n} \right)$

The correct Option is "All are correct"

For a first order reaction, $A \to products$, the rate of reaction at $\left[ A \right] = 0.2\;{\rm{M}}$ is $1.0 \times {10^{ - 2}}\;{\rm{mol}}\;{{\rm{L}}^{ - 1}}\;{\min ^{ - 1}}{\rm{.}}$ The half-life period for the reaction is

$Rate = k\left[ A \right]$ $\therefore \;\;k = \frac{{{{10}^{ - 2}}}}{{0.2}} = 5 \times {10^{ - 2}}$ $Now,\;\;{t_{1/2}} = \frac{{0.693}}{k} = \frac{{0.693}}{{5 \times {{10}^{ - 2}}}} = 13.86\;\min $

Rate of reaction depends upon

Rate of reaction depends upon nature of reactants, concentration of the reactants, temperature and presence of catalyst.

The correct Option is "All of these"

For a reaction, the rate of reaction was found to increase about 1.8 times when the temperature was increased by $10^\circ C$. The increase in rate is due to:

No doubt an increase in temperature may increase no. of collisions also but this is the increase in number of effective collisions (with more energy) which decide the rate.

The correct Option is "Increase in number of active molecules"

Increase in activation energy of reactants

Decrease in activation energy of reactants

Increase in the number of collisions between reacting molecules

For a gaseous reaction, the units of rate of rate of reaction are

For a gaseous reaction, the rate is written in terms of pressure change rather than concentration change, therefore, the rate of a gaseous reaction will be written in terms of ${\rm{atm}}\;{{\rm{s}}^{ - 1}}$

${\rm{L }}\;{\rm{atm}}\;{{\rm{s}}^{ - 1}}$

The correct Option is "${\rm{atm}}\;{{\rm{s}}^{ - 1}}$"

${\rm{atm}}\;{\rm{mo}}{{\rm{l}}^{ - 1}}\;{{\rm{s}}^{ - 1}}$

${\rm{mol}}\;{{\rm{s}}^{ - 1}}$

With increase in temperature, rate of reaction

With increase in temperature reaction rate increases due to increase in number of molecules having threshold energy.

The correct Option is "increases"

For the reaction, $2A + B \to products$, the active mass of B is kept constant, and that of A is doubled. The rate of reaction will be then

$2A + B \to products$, Rate of reaction, ${r_1} = k{\left[ A \right]^2}\left[ B \right]$ If the concentration of A become double then the rate will be ${r_2} = k{\left[ {2A} \right]^2}\left[ B \right]$ ${r_2} = 4k{\left[ A \right]^2}\left[ B \right]$ ${r_2} = 4\;{r_1}$

The correct Option is "Increase 4 times"

The rate of reaction becomes 2 times for every $10^\circ C$ rise in temperature. How the rate of reaction will increase when temperature is increased from $30^\circ C\;to\;80^\circ C?$

$\frac{{{K_{t + 10}}}}{{{K_t}}} = \frac{{{r_t} + 10}}{{{r_t}}} = 2;$ For an increase of temperature to $50^\circ C$, i.e., 5 times, the rate increases by ${2^5}$ times, i.e., $32$ times.

In homogeneous catalytic reactions, the rate of reaction :

Catalyst forms an intermediate with reactant and thus, rate of reaction for intermediate formation depends upon concentration of catalyst.

The correct Option is "Depends upon the concentration of catalyst"

Independent of the concentration of catalyst

Depends upon the free energy change

Depends upon physical state of the catalyst

Amongst the following which of the above are true for ${S_N}2\;$ reaction? (i) The rate of reaction is independent of the concentration of the nucleophile. (ii) The nucleophile attacks the carbon atom on the side of the molecule opposite to the group being displaced. (iii) the reaction proceeds with simultaneous bond formation and bond rupture

Follow characteristics of ${S_N}2$ mechanism.

The correct Option is "(ii), (iii)"

Rate of reaction, is fastest when $Z$ is

${\rm{C}}{{\rm{l}}^ - }$ is the best leaving group being the weakest nucleophile out of ${\rm{NH}}_2^ - ,{\rm{C}}{{\rm{l}}^ - },{{\rm{O}}^ - }$ $\begin{array}{l} \;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;{\rm{O}}\\ \;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;||\\ - {{\rm{C}}_2}{{\rm{H}}_5}\;and\;{{\rm{O}}^ - } - {\rm{C}} - {\rm{C}}{{\rm{H}}_3} \end{array}$

The correct Option is "${\rm{Cl}}$"

${\rm{O}}{{\rm{C}}_2}{{\rm{H}}_5}$

Two stamens as exception in Cruciferae are found in

Usually in Cruciferae family, six stamens are found in tetradynamous condition but in case of Senebiera sp, there are only two stamens

The correct Option is "Senebirea"

Which of the following are correct to describe viruses? I. Simple and unicellular organism. II. Contain DNA or RNA and enclosed by protein coat. III. Possess own metabolic system and respond to stimuli. IV. Maintain genetic continuity and undergo mutations. The correct combination is

Viruses are acellular, non-cytoplasmic structures and do not have own metabolic system because enzymes are absent. These have DNA or RNA and use host metabalic system.

The correct Option is "II and IV"

In wind pollination the pollens are feathery, whether it is

True, because due to the presence of feathers they can cover more distance

Sometimes (a) and sometimes (b)

Which one of the following is wrongly matched?

Pucciniais commonly called rust fungus. Smut is Ustilago. Both rust and smut belong to the class-Basidiomycetes.

The correct Option is "Puccinia– Smut"

Cassia– Imbricate aestivation

The enzyme part, which combines with non-protein part to form a functional enzyme, is known as

Functional form of enzymes is known as holoenzyme. It consists of a proteins part known as apoenzyme and non-protein part called prosthetic group (coenzyme of a metal ion).

The correct Option is "Apoenzyme"

Which of the following has epiphytic features and aerial and flattened photosynthetic roots, without formal organization of stem and leaves?

Taeniophyllum is an epiphytic orchid with thick, flattened, photosynthetic roots. These roots are green aerial, adventitious, which prepare food materials by photosynthesis. The stem and leaves are absent.

The correct Option is "Taeniophyllum"

The chromosome in which centromere lies slightly away from the middle of the chromosome resulting in one shorter arm and one longer arm, is called

The sub-metacentric chromosomes has centromere nearer to one end of the chromosome resulting in one shorter arm and one longer arm

The correct Option is "Submetacentric"

Why hierarchiral taxonomic system is used?

Hierarchical system is used in classification by majority of the biologist because each higher taxonomic category contain its below group, i.e., it reduce the volume of description in a catalogue of animal and plants and character at larger category need not to be repeated for smaller categories