Description : For a heterogeneous catalytic reaction (A) Free energy of activation is lowered in the presence of catalyst, which remains unchanged at the end of reaction (B) A relatively small amount of catalyst ... with the reactant (D) The surface of the catalyst does not play an important role during reaction
Last Answer : (A) Free energy of activation is lowered in the presence of catalyst, which remains unchanged at the end of reaction
Description : In photosynthesis is chlorophyll considered a reactant a product neither how does the role of chlorophyll compare with the roles of co2 and h20?
Last Answer : Need answer
Description : A spherical porous catalyst particle of radius R is subjected to reactant A which reacts to form B by a zero order surface reaction A → B. Film mass transfer resistance is negligible and pore diffusion of A ... (D) Effectiveness factor for a zero order reaction cannot be 7/8 as it must always be 1
Last Answer : (A) Inner catalyst core of radius R/8 does not participate in reaction (
Description : What purpose does FeCl3 serve in the electrophilic aromatic substitution reaction between chlorine and benzene? (a) It serves as a radical initiator to produce the chlorine radical needed to propagate the ... by reacting with the Cl2 and thereby activates it toward attack by benzene's π electrons.
Last Answer : It serves as a Lewis acid catalyst by reacting with the Cl2 and thereby activates it toward attack by benzene’s π electrons.
Description : Consider the following gaseous equilibrium: PCl3 + Cl2 = PCl5 + heat. Which of the following changes will shift it to the right: w) lower the temperature x) remove some Cl2 y) increase the volume z) add a catalyst
Last Answer : ANSWER: W -- LOWER THE TEMPERATURE
Description : In multistage equilibrium conversion of SO2 to SO3 (2SO2 + O2 ⇌ 2SO3 ), the reverse reaction becomes appreciable at a temperature of 550° C. The percentage equilibrium conversion of SO2 to ... some quantity of SO3 during intermediate stage (D) Maintaining low temperature & pressure in the converter
Last Answer : (C) Removing some quantity of SO3 during intermediate stage
Description : Two half-reactions of an electrochemical cell are given below : MnO-4 (aq) + 8H+ (aq) + 5e- → Mn2+ (aq) + 4H2O (I), E° = 1.51 V Sn2+ (aq) → Sn4+ (aq) + 2e- ... the redox equation from the standard potential of the cell and predict if the reaction is reactant favoured or product favoured. -Chemistry
Last Answer : The reactions can be represented at anode and at cathode in the following ways : At anode (oxidation) : Sn2+ → = Sn4+ (aq) + 2e- ] 5 E° = + 0.15 V At cathode (reduction) : MnO-4(aq) + 8H+ ... = E°cathode - E°anode = 1.51 - 0.15 = + 1.36 V ∴ Positive value of E°cell favours formation of product.
Description : Two half-reactions of an electrochemical cell are given below : MnO-4 (aq) + 8H+ (aq) + 5e- → Mn2+ (aq) + 4H2O (I), E° = 1.51 V Sn2+ (aq) → Sn4+ (aq) + ... -reactions and calculate the cell potential from the standard potentials and predict if the reaction is reactant or product favoured. -Chemistry
Last Answer : The reactions can be represented at anode and at cathode in the following ways : At anode (oxidation) : Sn2+ → Sn4+ (aq) + 2e- ] 5 E° = + 0.15 V Af cathode (reduction) : MnO-4(aq) + 8H+ ( ... = E°cathode - E°anode = 1.51 - 0.15 = + 1.36 V ∴ Positive value of E°cell favours formation of product.
Description : Identify the INCORRECT statement below regarding chemical equilibrium. A All chemical reactions are, in principle, reversible. B Equilibrium is achieved when the forward reaction rate equals the ... equilibrium constant. E Equilibrium is achieved when reactant and product concentrations are equal.
Last Answer : E Equilibrium is achieved when reactant and product concentrations are equal.
Description : During photosynthesis, energy is absorbed by chlorophyll, therefore it is: (a) exothermic reaction (b) endothermic reaction (c) neither exothermic nor endothermic reaction (d) the process takes place in plants only
Last Answer : (b) endothermic reaction
Description : In photosynthesis energy from light reaction to dark reaction is transferred in the form of (a) ADP (b) ATP (c) RuDP (d) chlorophyll.
Last Answer : (b) ATP
Description : A key energy compound in bacterial photosynthesis by cyanobacteria is ______ and a major end-product is ______. a. GTP; protein b. citrate; lactose c. glucose; chlorophyll d. ATP; glucose
Last Answer : c. glucose; chlorophyll
Description : Field capacity represents the maximum quantity of water held: w) in the soil against the force of gravity x) in the ground water zone y) in the intermediate zone z) below the water table
Last Answer : ANSWER: W -- IN THE SOIL AGAINST THE FORCE OF GRAVITY
Description : Which of the following refers to an easily melted product of the reaction between the flux and the impurities of an ore? w) slag x) slurry y) slug z) none of the above
Last Answer : ANSWER: W -- SLAG
Description : What reactant is missing in order for photosynthesis to occur?
Last Answer : What is the answer ?
Description : Which of these is a reactant in photosynthesis?
Last Answer : the answer is water
Description : The rate constant of a first order reaction depends on the (A) Concentration of the reactant (B) Temperature (C) Concentration of the product (D) Time
Last Answer : (B) Temperature
Description : Biomass energy is w) formed through photosynthesis x) caused by heat due to the large mass of the Earth y) has been used for only a few years z) the predominant source of commercial heat energy in the northern regions of the United States
Last Answer : ANSWER: W -- FORMED THROUGH PHOTOSYNTHESIS
Description : In an ocean, the upper layer of water with sufficient light penetration to support photosynthesis by aquatic plants i known as the: w) free zone x) plant zone y) photic zone z) primary zone
Last Answer : ANSWER: Y -- PHOTIC ZONE
Description : Biomass energy is: w) formed through photosynthesis x) caused by heat due to the large mass of the earth y) has been used for only a few years z) is effective in only certain regions of the United States
Description : Kinetics is the study of: (1) The rate of chemical reaction (2) How fast the reactions go (3) The mechanisms and paths of the molecules take in joining from one reactant to products (4) All of these are correct
Last Answer : (4) All of these are correct Explanation: In chemistry, the study of rates and mechanisms of chemical processes and, of the factors on which they depend, is called kinetics. is the study of ... provides a very detailed picture of which bonds are broken and formed during the course of a reaction.
Last Answer : All of these are correct
Description : Apart from sunlight and chlorophyll, what other things are required to make food by photosynthesis ? -Science
Last Answer : Carbon dioxide and water.
Description : The wavelength of light most absorbed by chlorophyll-a during photosynthesis is
Last Answer : The wavelength of light most absorbed by chlorophyll-a during photosynthesis is A. 460 nm B. 500 nm C. 600 nm D. 660 nm
Last Answer : The wavelength of light most absorbed by chlorophyll-a during photosynthesis is A. 400 nm B. 550 nm C. 660 nm D. 700 nm
Description : $ Nostoc has chloropyll "a" and phycocyanin pigments. ! Chlorophyll "a" helps in oxygenic photosynthesis.
Last Answer : $ Nostoc has chloropyll "a" and phycocyanin pigments. ! Chlorophyll "a" helps in oxygenic photosynthesis. A. ... wrong D. If both As and R are wrong.
Description : Chlorophyll is essential to photosynthesis because it traps the needed?
Last Answer : Chlorophyll traps the light energy from the sun
Description : Moll’s experiment explains that (a) Carbon dioxide is essential for photosynthesis (b) Chlorophyll and water are necessary for photosynthesis (c) Light and water are essential for photosynthesis (d) All of the above are correct
Last Answer : Ans. ((a))
Description : Which cell organelle is the site of photosynthesis and also contains chlorophyll? (1) chloroplasts (2) vacuole (3) cytoplasm (4) nucleolus
Last Answer : (1) chloroplasts Explanation: Chloroplast, found in plant cells, is the site of photosynthesis in plants to prepare food (glucose) for the plant with the use of energy. It is a green ... a and b that absorb visible light energy and convert it to usable chemical energy in photosynthesis.
Description : The liberation of oxygen during photosynthesis is due to - (1) hydrolysis of carbohydrates (2) photolysis of water (3) reduction of CO2 (4) breakdown of chlorophyll
Last Answer : (2) photolysis of water Explanation: In the process of photosynthesis, oxygen is produced from the photolysis of water. The photolysis of water occurs when light is used to renew split water and ... , also referred to as ATP. The hydrogen remains in the leaf and participates in further reactions.
Description : Which of the following provides energy for photosynthesis? (1) Water (2) Sunlight (3) Chlorophyll (4) Carbon dioxide
Last Answer : (2) Sunlight Explanation: Photosynthesis is a process used by plants and other organisms to convert the light energy captured from the sun into chemical energy that can be used to fuel the ... is therefore: Carbon dioxide + electron donor + light energy -4 carbohydrate + oxidized electron donor.
Description : The source of oxygen generated during photosynthesis is: (1) water (2) carbon dioxide (3) chlorophyll (4) mesophyll cells
Last Answer : (1) water Explanation: The source of oxygen produced during photosynthesis is the splitting of water molecule into hydrogen and oxygen. Photosynthesis uses carbon dioxide and water, releasing ... inside organelles called chloroplasts, while in bacteria they are embedded in the plasma membrane.
Description : Prove with experiment that chlorophyll is necessary for photosynthesis?
Last Answer : i) De-starch a leaf of potted plant by wrapping it in aluminum foil. ii) Remove the leaf from plant. iii) Its outline is carefully drawn to note the position of chlorophyll. iv) ... vii) If photosynthesis is possible without chlorophyll than white part should also turn blue.
Description : The first step for initiation of photosynthesis will be (a) photolysis of water (b) excitement of chlorophyll molecules due to absorption of light (c) ATP formation (d) glucose formation.
Last Answer : (b) excitement of chlorophyll molecules due to absorption of light
Description : Which of the following absorb light energy for photosynthesis? (a) Chlorophyll (b) Water molecule (c) O2 (d) RuBP
Last Answer : a) Chlorophyll
Description : Manganese is required in (a) plant cell wall formation (b) photolysis of water during photosynthesis (c) chlorophyll synthesis (d) nucleic acid synthesis.
Last Answer : d) nucleic acid synthesis.
Description : 6. __________ is a special constituent of chlorophyll without which photosynthesis is not possible. (A) Calcium (B) Nitrogen (C) Phosphorous (D) Hydrogen
Last Answer : Option B
Description : In chlorophyll-containing plants, what are TWO products of green plant photosynthesis?
Last Answer : ANSWER: OXYGEN AND GLUCOSE (accept energy, also)
Description : In the first stage of photosynthesis, light energy is used to: a) move water molecules b) denature chlorophyll c) split water d) produce carbohydrates
Last Answer : ANSWER: C -- SPLIT WATER
Description : The liberation of oxygen during photosynthesis is due to (1) hydrolysis of carbohydrates (2) photolysis of water (3) reduction of CO2 (4) breakdown of chlorophyll
Last Answer : photolysis of water
Description : The oxygen liberated during photosynthesis comes from (1) Water (2) Carbon dioxide (3) Glucose (4) Chlorophyll
Last Answer : Water
Last Answer : chloroplasts
Last Answer : Sunlight
Description : The source of oxygen generated during photosynthesis is : (1) water (2) carbon dioxide (3) chlorophyll (4) mesophyll cells
Last Answer : water
Description : The rate of a chemical reaction can be affected by: w) temperature x) concentration of products y) concentration of reactants z) all of the above
Last Answer : ANSWER: Z -- ALL OF THE ABOVE
Description : The equilibrium constant for the gas phase reactio A + B = C + D is 10-3. The rate of the forward reaction is 10-11 cubic centimeters per molecule per second. What is the rate constant of ... second y) 10-10 cubic centimeters per molecule per second z) 10-14 cubic centimeters per molecule per second
Last Answer : ANSWER: Z -- 10-14 CUBIC CENTIMETERS PER MOLECULE PER SECOND
Description : In protolytic reactions in which the reactants are much stronger as an acid and a base than the products, the proton transfer reaction: w) does not occur x) approaches completeness y) produces a much stronger acid and a much weaker base z) produces a much weaker acid and a much stronger base
Last Answer : ANSWER: X -- APPROACHES COMPLETENESS
Description : Which of the following chemical reactions does not lead to formation of a salt? w) Reaction of salts with acids. x) The reaction of base anhydrides with acid anhydrides. y) Action of water on oxides of nonmetals. z) Reaction of acid with base.
Last Answer : ANSWER: Y -- ACTION OF WATER ON OXIDES OF NONMETALS. (If water reacts with oxides of nonmetals, an acid is formed.)
Description : What two primary factors determine whether or no molecular collision leads to a chemical reaction? w) energy and volume of molecules x) energy and mass of molecules y) energy and orientation of molecules z) orientation and volume of molecules
Last Answer : ANSWER: Y -- ENERGY AND ORIENTATION OF MOLECULES