Using the data given below to find out
Question: Using the data given below to find out the strongest reducing agent. EᶱCr2O72-/Cr3+= 1.33V EᶱMnO4/Mn2+= 1.51V EᶱCl2/Cl= 1.36V EᶱCr3+/Cr = -0.74V (i) Cl (ii) Cr (iii) Cr3+ (iv) Mn Solution: Option (ii)Cris the answer....
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Question: Show that the relation $R$ defined on the set $A=(1,2,3,4,5)$, given by $R=\{(a, b):|a-b|$ is even $\}$ is an equivalence relation. Solution: In order to show $R$ is an equivalence relation we need to show $R$ is Reflexive, Symmetric and Transitive. Given that, $\forall a, b \in A, R=\{(a, b):|a-b|$ is even $\}$. Now, $\underline{R}$ is Reflexive if $(a, a) \in \underline{R} \underline{\forall} \underline{a} \in \underline{A}$ For any a $\in A$, we have $|a-a|=0$, which is even. $\Righ...
Read More →Which of the statements about solutions of electrolytes
Question: Which of the statements about solutions of electrolytes is not correct? (i) The conductivity of the solution depends upon the size of ions. (ii) Conductivity depends upon the viscosity of the solution. (iii) Conductivity does not depend upon solvation of ions present in solution. (iv) The conductivity of the solution increases with temperature. Solution: Option (iii)Conductivity does not depend upon solvation of ions present in solution is the answer....
Read More →An electrochemical cell can behave like
Question: An electrochemical cell can behave like an electrolytic cell when ____________. (i) Ecell = 0 (ii) Ecell Eext (iii) Eext Ecell (iv) Ecell = Eext Solution: Option (iii)Eext Ecell is the answer....
Read More →Which of the following statement is not correct
Question: Which of the following statement is not correct about an inert electrode in a cell? (i) It does not participate in the cell reaction. (ii) It provides surface either for oxidation or for the reduction reaction. (iii) It provides a surface for conduction of electrons. (iv) It provides a surface for a redox reaction. Solution: Option (iv) It provides a surface for a redox reactionis the answer....
Read More →Evaluate the integral
Question: Evaluate the integral $\int \frac{5 \cos x+6}{2 \cos x+\sin x+3} d x$ Solution: Ideas required to solve the problems: * Integration by substitution: A change in the variable of integration often reduces an integral to one of the fundamental integration. If derivative of a function is present in an integration or if chances of its presence after few modification is possible then we apply integration by substitution method. * Knowledge of integration of fundamental functions like sin, co...
Read More →The difference between the electrode potentials
Question: The difference between the electrode potentials of two electrodes when no current is drawn through the cell is called ___________. (i) Cell potential (ii) Cell emf (iii) Potential difference (iv) Cell voltage Solution: Option (ii)Cell emfis the answer....
Read More →Which of the following statement is correct?
Question: Which of the following statement is correct? (i) ECell and ∆rG of cell reaction both are extensive properties. (ii) ECell and ∆rG of cell reaction both are intensive properties. (iii) ECell is an intensive property while ∆rG of cell reaction is an extensive property. (iv) ECell is an extensive property while ∆rG of cell reaction is an intensive property. Solution: Option (iii)ECell is an intensive property while ∆rG of cell reaction is an extensive propertyis the answer....
Read More →Which cell will measure standard electrode
Question: Which cell will measure standard electrode potential of copper electrode? (i) Pt (s) H2(g,0.1 bar) H+ (aq.,1 M) Cu2+(aq.,1M) Cu (ii) Pt(s) H2 (g, 1 bar) H+ (aq.,1 M) Cu2+ (aq.,2 M) Cu (iii) Pt(s) H2(g, 1 bar) H+ (aq.,1 M) Cu2+ (aq.,1 M) Cu (iv) Pt(s) H2 (g, 1 bar) H+(aq.,0.1 M) Cu2+ (aq.,1 M) Cu Solution: Option (iii)Pt(s) H2(g, 1 bar) H+ (aq.,1 M) Cu2+ (aq.,1 M) Cu is the answer....
Read More →Evaluate the integral
Question: Evaluate the integral $\int \frac{1}{\mathrm{p}+\mathrm{q} \tan \mathrm{x}} \mathrm{dx}$ Solution: Ideas required to solve the problems: * Integration by substitution: A change in the variable of integration often reduces an integral to one of the fundamental integration. If derivative of a function is present in an integration or if chances of its presence after few modification is possible then we apply integration by substitution method. * Knowledge of integration of fundamental fun...
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Question: Let $R=\{(a, b): a, b \in Z$ and $(a-b)$ is divisible by 5$\}$ Show that $\mathrm{R}$ is an equivalence relation on $\mathrm{Z}$. Solution: In order to show $R$ is an equivalence relation, we need to show $R$ is Reflexive, Symmetric and Transitive. Given that, $\forall a, b \in Z, a R b$ if and only if $a-b$ is divisible by $5 .$ Now, $\underline{R}$ is Reflexive if $(a, a) \in \underline{R} \underline{\forall} \underline{a} \in \underline{Z}$ $\mathrm{aRa} \Rightarrow(\mathrm{a}-\math...
Read More →Match the terms given in Column I
Question: Match the terms given in Column I with expressions given in Column II. Solution: (i) is d (ii) is c (iii) is b (iv) is e (v) is a...
Read More →Evaluate the integral
Question: Evaluate the integral $\int \frac{3+2 \cos x+4 \sin x}{2 \sin x+\cos x+3} d x$ Solution: Ideas required to solve the problems: * Integration by substitution: A change in the variable of integration often reduces an integral to one of the fundamental integration. If derivative of a function is present in an integration or if chances of its presence after few modification is possible then we apply integration by substitution method. * Knowledge of integration of fundamental functions lik...
Read More →Match the laws given in Column I
Question: Match the laws given in Column I with expressions given in Column II. Solution: (i) is c (ii) is e (iii) is d (iv) is a (v) is b...
Read More →Match the items given in Column I with
Question: Match the items given in Column I with the type of solutions given in Column II. Solution: (i) is e (ii) is c (iii) is d (iv) is b (v) is a...
Read More →Match the items given in Column I and Column II.
Question: Match the items given in Column I and Column II. Solution: (i) is d (ii) is c (iii) is a (iv) is b (v) is f (vi) is e...
Read More →Give an example of a material used for making
Question: Give an example of a material used for making semipermeable membrane for carrying out reverse osmosis. Solution: Examples of materials used for the semipermeable membrane include cellulose acetate and polyamides....
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Question: Let $R=\{(a, b): a, b \in Z$ and $(a+b)$ is even $\} .$ Show that $R$ is an equivalence relation on $Z$. Solution: In order to show $R$ is an equivalence relation, we need to show $R$ is Reflexive, Symmetric and Transitive. Given that, $\forall a, b \in Z, R=\{(a, b):(a+b)$ is even $\}$ Now, $\underline{R}$ is Reflexive if $(a, a) \in \underline{R} \underline{\forall} \underline{a} \in \underline{Z}$ For any $a \in A$, we have $a+a=2 a$, which is even. $\Rightarrow(a, a) \in R$ Thus, $...
Read More →What is a “semi-permeable membrane”?
Question: What is a semi-permeable membrane? Solution: A semipermeable membrane is a membrane that allows only the flow of solvent molecules but not solute molecules. Cellulose acetate and phospholipid bilayer in biological cells are the examples for semi-permeable membrane....
Read More →How does sprinkling of salt help in clearing
Question: How does sprinkling of salt help in clearing the snow-covered roads in hilly areas? Explain the phenomenon involved in the process. Solution: Salt is a de-icing agent and can be used to melt ice. If the freezing point is lowered the ice starts melting. So the addition of salt to snow reduces the freezing point from O℃ to lower....
Read More →Why is the vapour pressure of an aqueous
Question: Why is the vapour pressure of an aqueous solution of glucose lower than that of water? Solution: Example of water and glucose can be taken for explaining this. In water, the surface of the liquid will be occupied by the water molecules. When we add glucose into it, some of the surfaces will be occupied by the glucose molecules. Therefore the number of a solvent molecule will escape from the surface and thus vapour pressure also get reduced....
Read More →(a) Explain the following phenomena with
Question: (a) Explain the following phenomena with the help of Henrys law. (i) A painful condition known as bends. (ii) Feeling of weakness and discomfort in breathing at high altitude. (b) Why soda water bottle kept at room temperature fizzes on opening? Solution: (i) Bends is a condition that occurs to sea drivers or scuba drivers. They have to breathe air under high pressure underwater. Nitrogen gas is not soluble at normal pressure. In underwaters, they dissolve in the blood. Once the divers...
Read More →Why are aquatic species more comfortable
Question: Why are aquatic species more comfortable in cold water in comparison to warm water? Solution: Aquatic species are more comfortable in cold water due to the increased solubility and availability of O2....
Read More →What is the significance of Henry’s
Question: What is the significance of Henrys Law constant KH? Solution: Henrys law states that in a solution, the partial pressure of the gas in the vapour phase (p) is proportional to the mole fraction of the gas (x) in the solution The equation is given as p = KHx, where KH is the Henry Laws constant. The constant is a function of the nature of the gas. If kH value is high at a given temperature, then lower will be the solubility of a gas in the liquid....
Read More →Concentration terms such as mass percentage,
Question: Concentration terms such as mass percentage, ppm, mole fraction and molality are independent of temperature, however, molarity is a function of temperature. Explain. Solution: A change in temperature causes a change in volume, therefore changes the molarity of a solution. Hence, terms such as mass percentage, ppm, mole fraction, and molality are independent of temperature as they are calculated based on mass and do not involve volume....
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