InterviewSolution
This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 91901. |
A 0.01m aqueous solution of AlCL_3 freezes at -0.068^@C Calculate the percentage of dissociation. |
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Answer» SOLUTION :USE the relation : `Delta T_f=iK_fm`, where I is van.t Hoff factor. Given that `m=0.01 , Delta T_f=0.068^@C, K_f=1.86K kg mol^-1` Substituting the values in the above equation, we have `0.068 k=1 times 86 k kg mol^-1 times 0.01 mol kg^-1` or `i=0.068/(1.86 times 0.01)3.6559`....(i) `AlCl_3 to AL^(3+)+3Cl^(-)` 1-x x 3X `i=(1+3x)/1` From (i) and (ii), we have `1+3x=3.6559 or 3x=2.6559 or x=0.8853` Percentage of dissociation =`0.8853 times 100=88.53` |
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| 91902. |
._(6)^(13)C and ._(7)^(14)N are the |
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Answer» Isotopes |
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| 91903. |
A 0.010 M solution of maleic acid, amonoprotic organic acid, is 14% ionized. What is K_(a) for maleic acid |
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Answer» `2.3 xx 10^(-3)` |
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| 91904. |
6.0xx10^(20) molecules of urea are present in 100 L of his solution. The concentration of urea solution is |
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Answer» 0.001 M `:. 10^(-3)` mol of urea are present in 100 ML `:.` Moles of urea present in 1L (1000 mL) `=10^(-3)xx10=10^(-2)` `:.` Molarity of solution `= 10^(-2) M = 0.01 M` |
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| 91905. |
A 0.01 M solution of glucose in water freezes at- 0.0186^(@)C. A 0.01 M solution of NaCl in water will freeze at |
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Answer» `0^(@)C` |
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| 91906. |
60g ofcompound on analysis gave C= 24g, H= 4 g and O = 32g. If Empirical formula is |
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Answer» `C_(2)H_(4)O_(2)` Therefore `CH_(2)O`. |
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| 91907. |
A 0.01 M ammonia solution is 5% ionized. The concentration of OH^- ion is: |
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Answer» 0.005 M |
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| 91908. |
A 0.01 M ammonia solution is 5% ionized, the concentration of OH^(-) ion is : |
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Answer» 0.005 M `[OH^(-)]=0.01xx0.05 = 0.0005 M` |
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| 91909. |
6.02 xx 10^(20) molecules of urea are present in 100 mL of its solution. The concentration of urea solution is (Avogadro constant, N_(A) = 6.02 xx 10^(23)mol^(-1)) |
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Answer» 0.02 M =0.001 mol. 100 mL of solution has moles = 0.001 1000 mL of solution has moles `=(0.001)/((10ML))XX(1000mL)=0.01 M.` |
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| 91910. |
(6.023xx10^(23)xx1)/10^(20)=6023 sec=1.673 hrs. A 100% pure sample of a divalent metal carbonate weighing 2g on complete thermal decomposition releases 448 cc of carbon dioxide at STP. The equivalent mass of the metal is |
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Answer» 40 `{:(ACO_(3) overset(Delta )(rarr)MO+CO_(2)),("1 mol22400 CC"),("2 g448 cc"),("448 cc evolves from 2g"):}` 22400 cc will evolve from `2/448xx22400g=100g` i.e., 100 G is the MOLECULAR weight of the carbonate. Then M.W. of metal `=100-(12+3xx16)` (wt. of carbonate, `CO_(3)^(2-)`) `=40 g` Equivalent weight `=("Molecular weight")/("Valency")` `=40/2=20`. |
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| 91911. |
A 0.004 M Solution of Na_(2)SO_(4) is isotonic with a 0.010 M solution of glucose at the temperature. The apparent degree of dissociation of Na_(2)SO_(4) is |
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Answer» Solution :`pi(Na_(2)SO_(4))=iCRT=i(0.004)RT` `pi"(Glucose) = CRT = 0.010 RT"` As solution are isotonic, I (0.004) RT = 0.01 RT. This givesI = 2.5 `{:("Now",Na_(2)SO_(4),hArr,2Na^(+),+,SO_(4)^(2-)),(,"1 MOLE",,0,,0),(,1-alpha,,2ALPHA,,alpha","):}` `"Total "=1+2alpha` `therefore""i=1+2alpha` `"or"alpha=(i-1)/(2)=(2.5-1)/(2)=0.75=75%`. |
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| 91912. |
A 0.01 D^(**) solution of KCl has a specific conductance value of 0.00141 mho cm^(-1). A cell filled with this solution has a resistance of 42156 ohms. (a) What is the cell constant ? (b) The same cell filled with a solution of Hcl has a resistance of 1.0326 ohms. What is specific conductivity of the HCl solution ? |
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Answer» Solution :(a) Cell constant `= ("specific conductance")/("conductance")` `= ("specific conductance")/("1/resistance")` `= (0.00141)/(1//4.2156) = 0.00594 CM^(-1)`. (b) Conductance of HCL solution `= (1)/(1.0326)` mho. Sicne the same cell is USED, we SHALL take the same value of cell constant in this case. SP. conductance = cell constant `xx` conductance `= 0.00594 xx (1)/(1.0326)` `= 0.00575 "mho cm"^(-1)`. |
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| 91913. |
6.02xx10^(20) molecules of urea are present in 100 mL of its solution. The concentration of the solution is |
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Answer» 0.02 M `=(6.02xx10^(20))/(6.20xx10^(23))=10^(-3)"MOL"` `therefore` Molar CONCENTRATION of urea in the solution `=(10^(-3))/(100)xx1000=10^(-2)M=0.01M` |
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| 91914. |
6.022 xx 10^(22) molecules of N_2 at NTP will occupy a volume of |
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Answer» 2.234 litre |
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| 91915. |
A 0.004 M solution of Na_(2)SO_(4) is isotomic with a 0.01 M solution of glucose at same temperature. The apparent degree of dissociation of Na_(2)SO_(4) is: |
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Answer» Solution :Since the SOLUTIONS are ISOTONIC, They have the same osmotic pressure also. `pi_(Na_(2)SO_(4))=pi_("glucose")` `ixx0.004 RT = 0.01 RT` `i=0.01/0.004=2.5` `Na_(2)SO_(4)hArr2Na^(+)+SO_(4)^(2-)` `ALPHA=(i-1)/(n-1)=(2.5-1)/(3-1)=1.5/2` =0.75 or 75% |
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| 91916. |
6.02 xx10^(20) molecules of urea are present in I 00 ml of its solution. The concentration of urea solution is |
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Answer» `0.02 M ` |
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| 91917. |
6.02 xx 10^20 molecules of urea are present in 100 mL. of its solution. The concentration of solution is |
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Answer» 0.1M |
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| 91918. |
A 0.004 M solution of Na_(2)SO_(4) is isotonic with 0.010 M solution of glucose at same temperature. The percentage dissociation of Na_(2)SO_(4) is |
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Answer» 0.25 Since both SOLUTIONS are ISOTONIC, therefore, `0.004 + 2x = 0.01, x = 3 xx 10^(-3)` `:.` % DISSOCIATION `= (3 xx 10^(-3))/(0.004) xx 100 = 75` |
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| 91919. |
6.02 xx 10^20molecules of urea are present in 100ml of its solution. The concentration of solution is |
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Answer» 0.02 M Molarity ` = (10^(-3) )/(100) xx 1000 = 0.01 M` |
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| 91920. |
600 mL of aqueoussolutioncontining2.5g of a protein shows an osmotic pressureof 25mm Hg at 27^(@)C.Determinethe molecular mass of protein. |
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Answer» `w_(2) = 2.5 g , R = 0.0821 L atm mol^(-1) K^(-1)` ` T= 273 + 27 = 300 K` ` pi = (25)/(760) atm ,V = (600)/(1000) L` `M_(2)= ((2.5 g xx 0.0821 L atm mol^(-1)K^(-1)) xx (300K))/(((25)/(760) atm) xx((600)/(1000)L))` ` = 3119.8 g mol^(-1)` |
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| 91921. |
A 0.004M solution of Na_(2)SO_(4) is isotonic with a 0.010 M solution of glucose at same temperature. The apparent degree of dissociation of Na_(2)SO_(4) is |
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Answer» `25%` |
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| 91922. |
60 mL of a mixture of nitrous oxide and nitric oxide was exploded with excess of hydrogen. If 38 mL of N_(2) was formed calculated the volume of each gas in the mixture |
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Answer» SOLUTION :`V_(NO)=44 mL` `V_(N_(2)O)=16 mL` |
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| 91923. |
6.0 g of urea (molecular weight = 60) was dissolved in 9.9 moles of water. If the vapour pressure of pure water is p_(0), the vapour pressure of solution is |
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Answer» `0.10 p_(0)` ACCORDING to Raoult's law `(p_("solvent") - p_("solution"))/(p_("solvent")) = x_("SOLUTE") = (n_(A))/(n_(A) + n_(B))` Hence, `(p_(0) - p_("solution"))/(p_(0)) = (0.10)/(0.10 + 9.9)` or `p_(0) - p_("solution") = 0.01 p_(0)` or `p_("solution") = 0.99 p_(0)` |
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| 91924. |
6 moles of 'A' and 10 moles of 'B' are mixed and allowed to react according to the equation. A+3Brarr2C How many moels of C are present when there are 4 moles of A in the container? |
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Answer» |
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| 91925. |
A 0.0020 m aqueous solution os an ionic compound [Co(NH_(3))_(5)(NO_(2))] CI freezes at -0.0732^(@)C. Number of moles of ions which 1 mole of an ionic compound produces on being dissolved in water will be: |
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Answer» 3 `i=((0.0732K))/((1.86Km^(-1))xx(0.0020m))=2` Since, the ionic compound complete dissociates in aqueous OLUTION, DEGREE of dissociation `(PROP)is ~~1`. For dissociation, `ALPHA=(i-1)/(n-1)` `1=(2-1)/(n-1)or n=1+1=2` No. of mole ions formed=2 |
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| 91926. |
6 moles of an ideal gas expand isothermally and reversibly from a volume of 1 litre to a volume of 10 litres at 27^(@)C. What is the maximum work done |
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Answer» 47 kJ `W=-2.303 nRTlog.(V_(2))/(V_(1))` `=-2.303xx6xx8.314xx300log.(10)/(1)` =34464.8 JOULE = 34.465 kJ. |
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| 91927. |
6 mole of ethyl alcohol reacts with sodium metal. How many moles of hydrogen are liberated ? |
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Answer» 2 |
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| 91928. |
A 0.0020m aqueous solution of an ionic compound Co(NH_(3))_(5)(NO_(2))Clfreezes at -0.00732^(@)C. Number of moles of ions which 1 mol of ionic comound produces on being dissolved in water be (K_(f)=-1.86^(@)C//m) |
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Answer» 2 `i=(Delta T_(f))/(k_(f)xxm)=(0.00732)/(1.86xx0.002)=2`. |
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| 91929. |
A 0.0020 m aqueous solution of an ionic compound Co(NH_(3))_(5) (NO_(2))Cl freezes at -0.00744^(@)C. The number of moles of ions which 1 mole of ionic compound produces on being dissolve in water is (K_(f)=-1.86^(@)C//m) |
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Answer» `because T_(F)=K_(f)i.m.` `therefore i=(T_(f))/(K_(f)xxm)=(0.00744)/(1.86xx0.0020)=2`. |
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| 91930. |
A 0.0020 M aqueous solution of an ionic compound Co(NH_(3))_(4)(NO_(2))_(2)Cl freeze at - 0.00732^(@)C. Number of moles of ions which 1 mol of ionic compound produces on being dissolved in water will be (K_(f)=1.86^(@)C//m). |
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Answer» 3 `DeltaT_(F)=iK_(f)m, i=DeltaT_(f)//K_(f)m` `DeltaT_(f)=0-(-0.00732)` `=0.00732^(@)C` `K_(f)=1.86^(@)C//m` `m=0.0020` `i=(0.00732)/(1.86xx0.0020)` `=1.96~~2` |
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| 91931. |
A 0.0020 m aqueous solution in an ionic compound Co(NH_3)_5 (NO_2)Clfreezes at -0.00732^@C. Number of moles of ions which 1 mol of ionic compound produces on being dissolved in water will be (K_f=+1.86^@ C/m) |
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Answer» 1 |
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| 91932. |
6 grams of a substance 'A' dissolved in 100 g of water freezes at - 0.93^(@)C. Themolecular mass of 'A' is (K_(f)=1.86 Km^(-1)). |
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Answer» 60 `M_(B)=(K_(f)xx1000xx w_(B))/(w_(A)XX Delta T_(f))` `=(1.86xx1000xx6)/(100 xx 0.93)=120` |
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| 91933. |
A 0.001 molal solution of a complex with molecular formula [Pt(NH_(3))_(4)Cl_(4)] in water showed a freezing point depression of 0.0054^(@)C. If K_(f) for water is 1.80, what is the correct formulation of the molecule with a proper coordination sphere? |
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Answer» SOLUTION :Suppose `[Pt(NH_(3))_(4)Cl_(4)]OVERSET("Dissociation")RARR" n moles of product ions "therefore""i=n` Substituting the given data in the formula, `DeltaT_(f)=iK_(f)m`, we get `0.0054=nxx1.80xx0.001"or"n=3` Hence, the formula MUST be one which gives 3 ions of the products, i.e., `[Pt(NH_(3))_(4)Cl_(2)]Cl_(2)` `([Pt(NH_(3))_(2)Cl_(2)]Cl_(2)rarr[Pt(NH_(3))_(4)Cl_(2)]^(2+)+2Cl^(-))` |
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| 91934. |
6 gm nitrogen on successive reaction with different compounds gets finally converted into 30 gm [CR(NH_(3))_(x)Br_(2)] value of x is [ Atomic mass of Cr = 52, Br =80] |
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Answer» |
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| 91935. |
A 0-05 M sodium hydroxide offered a resistance of 31.6Omega in a conductivity cell at 298 K. Calculate the molar conductance (cell constant of cell =0367cm^(-1)). |
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Answer» Solution :Specific conductance (K) `=("CELL CONSTANT")/(R)` `R=31.6Omega` Cell constant `=0.367cm^(-1)` Specific conductance, (k) `=(0.367)/(36.1)=0.0116Omegacm^(-1)` Molar conductance, `Delta_(m)=(1000xxk)/(M)` `=(1000xx0.0116)/(0.08)=232ohm^(-1)cm^(2)mol^(-1)` |
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| 91936. |
6 g urea is dissolved in 90 g water. The relative lowering of vapour pressure is equal to: |
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Answer» 0.0196 |
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| 91937. |
6 g of urea is dissolved in 90g of boiling water. The vapour pressure of the solution is |
| Answer» Answer :A | |
| 91938. |
99% of a first order reaction was completed in 32 in. When wil 99.9% of the reaction complete? |
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Answer» 50 min |
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| 91939. |
6 g ofH_(2) reacts with 14 g N_(2)to form NH_(3)till the reaction completely consumes the limiting reagent. The mass of other reactant (in g) left are …… |
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Answer» GIVEN moles : `(6)/(2) = 3 ""(14)/(28) = 0.5` 3 mol of`H_(2)`REQUIRED 1 mol of`N_(2)`so `N_(2)`is the limiting REAGENT. 0.5 mol of `N_(2)`.will REACT with 1.5 mol`H_(2)`. So 1.5 mol`H_(2)`will be left. Mass of 1.5 mol`H_(2) = 2 xx 1.5 g = 3g` |
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| 91940. |
6 g of the organic compound on heating with NaOH gave NH_(3 which is neutralised by 200 ml of 1 NHCl. Percentage of nitrogen is : |
| Answer» SOLUTION :N//A | |
| 91941. |
6 g of a substance is dissolved in 100 g of water depresses the freezing point by 0.93^(@)C. The molecular mass of the substance will be: (K_(f) for water= 1.86^(@)C/molal) |
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Answer» 60 g/mole |
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| 91942. |
6 - 8% solution of acetic acid in water is called _______. |
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Answer» Vinegar |
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| 91943. |
99% of a 1st order reaction completed in 2.303 minutes. What is the rate constant and half life of the reaction |
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Answer» 2.303 and 0.3010 |
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| 91945. |
""_(98)Cf^(246) was formed along with a neutron when an unknown radioactive substance was bombarded with ""_(6)C^(12). The unknown substance was |
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Answer» `""_(91)Pa^(234)` `""_(Z)^(A)Q + ""_(6)^(12)C to ""_(98)^(246)Cf + ""_(0)^(1)N` `:. Z + 6 = 98 implies Z = 92` `A + 12 = 246 + 1 implies A = 235` So, the unknown substance is `""_(92)^(235)U`. |
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| 91946. |
5ml of standard gold sol, needs 0.5 mg of gelation for its protection from coagulation, calculate the gold no of gelation. |
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Answer» 1 `10ML` of gold sols. Required gelatin for protection from coagulation `=(0.5xx10)/(5)=1` |
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| 91947. |
0.8g of H_(2)SO_(4) is present in 2 litres of a solution. The molarityof the solution is |
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Answer» 0.1 M |
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| 91948. |
5mL of acetone is mixed with 100mL of H_(2)O. The vapour pressure of water above the solution is |
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Answer» <P>equal to the vapour PRESSURE of pure water In a solution `x_(A) lt 1` `:. p_(A) lt p_(A)^(@)` |
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| 91949. |
98% H_2SO_4 is: |
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Answer» Pyrosulphuric acid |
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| 91950. |
9.7xx10^(17) atoms of iron weigh as much as 1 cc of H_(2) at S.T.P. What is the atomic mass of iron? |
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Answer» Thus, `9.7xx10^(17)` atoms or iron have mass `=9.0xx10^(-5)g` `therefore" Mass of ONE mole, i.e., "6.02xx10^(23)" atoms of Fe"=(9.0xx10^(-5)xx6.02xx10^(23))/(9.7xx10^(17))=55.9g` |
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