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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.
| 50701. |
A base ball of mass 200g is moving with a velocity of 30 xx 10^(2) m s^(-1). If we can locate the base ball with an error equal to the wavelength of the light used (5000 Å), how will the uncertainty in momentum be compared with the total momentum of the base ball ? |
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Answer» `Delta x. Delta p = h//4p pi`. Calculate `DELTAP`. ALSO `p - MV`. Calculate `Delta p//p` |
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| 50702. |
A baloon is filled with hydrogen at room temperature. It will burst if pressure exceeds 0.2 bar . If at 1 bar pressure the gases occupies 0.30 L volume , upto what volume can the balloon be expanded by filling H_(2)? |
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Answer» Solution :Here `P_(1)=1 "BAR" P_(2) 0.2"bar"` `V_(1)=0.30L v_(2)=?` From Boyle.s law equation: `P_(1)v_(1)=P_(2)v_(2)` `:.v_(2)=(P_(1)V_(1))/(P_(2))=(1xx0*30)/(0*2)=1*5L` Since the baloon bursts at 0.2 bar pressure. Here the valume of ballon should REMAIN less than `1.5L`. |
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| 50703. |
A balloon of diameter 21 meter weight 100 kg. Calculate its pay-load, if it is filled with He at 1.0 atm and 27°C. Density fair is 1.2 kg m^(-3) (Given : R = 0.0821 L atm K^(-1)mol^(-1)) |
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Answer» 4952.42 kg wt. of balloon = `10^5` gm. wt of the in balloon = `(pvm)/(RT) = 78.87 xx 10^4 gm`. Total wt of GAS and balloon = `88.87 xx 10^4 gm` wt of AIR DISPLACED = `1.2 xx 4851 = 5821.2 kg`. PAYLOAD = `W_(("air displaced")("Balloon + gas"))` `= 5821.2 - 888.7 = 4932.42 kg . |
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| 50704. |
A balloon is filled withn hydrogen at room temperature. It will burst, if pressure exceeds 0.2 bar. If a 1 bar pressure the gas occupied 2.27 L volume, up to what volume can the ballon be expanded ? |
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Answer» Solution :(b) ACCORDING to Boyel's LAW,`p_(1)V_(1)=p_(2)V_(2)` `V_(2)=(p_(1)V_(1))/(p_(2))=(1 "BAR"xx2.27 L)/(0.02"bar")=11.35 L` |
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| 50705. |
A balloon is filled with hydrogen gas at room temperature. It will burst if pressure exceeds 0.2 bar. If at1 bar pressure the gas occupies 2.27L volume, upto what volume can the balloon be expanded? |
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Answer» <P> Solution :`P_(1)V_(1)=P_(2)V_(2),P_(1)=1` BAR `V_(1)=2.27L,P_(2)=0.2` bar `V_(2)=? V_(2)=(P_(1)V_(1))/(P_(2))=(1xx2.27)/0.2=11.35L` |
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| 50706. |
A balloon is filled with one mole of helium at 0^@C and 1 bar pressure. It will burst if pressure is decreased to 0.2 bar. What is the maximum volume of balloon? |
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Answer» Solution :At `0^@ C` and 1 BAR, GMV = 22.7L Boyle.s law is given as, `P_1V_1= P_2 V_2 ` `P_1 = 1"bar"V_1= 22.7L` `P_2= 0.2" bar" V_2 =?` The MAXIMUM volume of BALLOON = `V_2=(P_1 V_1)/(P_2) = ( 1 x 22.7 )/( 0.2 ) = 113.54 L` |
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| 50707. |
A balloon is filled with hydrogen at room temperature. It will burst if pressure exceeds 0.2bar. If at 1bar pressure the gas occupies 2.27 L volume, upto what volume can the ballon be expanded? |
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Answer» SOLUTION :According to Boyle.s LAW `p_1V_1 = p_2 V_2` If `p_1` is 1 BAR, `V_1` is 2.27L If `p_2` = 0.2 bar, then `V_2 = p_1V_1/p_2 = V_2 = 1BAR xx 2.27L/0.2bar = 11.35 L` SINCE balloon bursts at 0.2 bar pressure, the volume of balloon should be lass than 11.35L |
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| 50708. |
A balloon is filled with hydrogen at room temperature. It will burst if pressure exceeds 0.2 bar. If at 1 bar pressure the gas occupies 2.27 L volume,upto what volume can the balloon be expanded ? |
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Answer» <P> Solution :At PRESSURE `P_(1)`=1 bar,volume `V_(1)`=2.27 LAtpressure `P_(2)=0.2` bar, volume `V_(2)`=To be CALCULATED As temperature remains constants at room temperature, applying Boyle's law, `P_(1)V_(1)=P_(2)V_(2)` (1 bar)(2.27 L)=(0.2 bar)`V_(2)`or`V_(2)=(2.27)/(0.2)L=11.35L` Thus, the balloon can be EXPANDED upto 11.35 L. Beyond this volume it will burst. |
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| 50709. |
A balloon is filled with hydrogen at room temperature. It will burst if pressure exceeds 0.2 bar. If at 1 bar pressure the gas occupies 2.27 L volume, upto what volume can be balloon be expanded ? |
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Answer» Solution :Expansion of gas in balloonb mass (n) and temperature (T) remains constant. So Boyle.s low uses. Asccording to Boyle.s law, `p_(1)V_(1)=p_(2)V_(2)` where `p_(1)=` Initial PRESSURE = 1 BAR `V_(1)=` Initial volume = 2.7 L `p_(2)=` Final Pressure = Initial pressure + Increase in pressure = 1 bar + 0.2 bar = 1.2 bar `V_(2)=` Final volume (when it will burst) `therefore V_(2) = (p_(1)V_(1))/(p_(2))=(("1 bar")(2.7 L))/("1.2 bar")=11.35 L` It pressure INCREASES at 0.2 bar it will burst so its volume is less than 11.35 LIT. |
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| 50710. |
A balloon filled with acetylene is kept in a vessel of hydrogen at the same temperature and pressure. If the balloon is punctured with a pin, it |
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Answer» collapses |
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| 50711. |
A balloon blown up has a volume of 500 mL at 5^@C. The balloon is distended to 7/8th of its maximum capacity.Calculate the minimum temperature above which it will burst. |
| Answer» SOLUTION :`44.7^@C` | |
| 50712. |
A + B rarr C+D, Delta H = -10,000 J mol^(-1) , Delta S = - 33.3 J mol^(-1) K^(-1) (i) At what temperature the reaction will occur spontaneously from leftto right ? (ii) At what temperature , the reaction will reverse? |
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Answer» Solution :`DELTA G = DeltaH -T DeltaS` At EQUILIBRIUM , `Delta G =0` so that `Delta H = T Delta S` or `T = (DeltaH)/(DeltaS) = (- 10000J mol^(-1))/( - 33.3JK^(-1)mol^(-1))= 300.3K` (i) For spontaneity from left to right, `Delta G` should be -ve for the GIVEN REACTION. This willbe so if `T lt 300.3K` ( becasue `Delta H` and `Delta S` both are -ve ) (ii) For reverse reaction to occur, `Delta G` shouldbe `+` be for forward reaction. This will be so if `Tgt300.3` K. |
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| 50713. |
A+B hArr C+D is 100. If intially the concentrations of A and B are equal but at equilibrium concentration of D will be twicethatof A, then whatwill be the equilibrium constantof the reaction ? |
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Answer» `4//9` But we are given that `x= 2 (a-x)` or` 3 x = 2 a or a=3/2x = 1.5 x ` ` :. K= (x xx x)/(a-x^(2))= x^(2)/(1.5 x - x)^(2) = x^(2)/(0.25 x^(2))=4` |
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| 50714. |
A+B Compound (A) and (B) can be differentiated by : |
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Answer» 2- 4 -DNP B= `CH_(3)-overset(O)overset(||)C-CH_(3)obtained by hydrolysis of ehter. Fehling is used to differentiate aldehyde and KETONE. |
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| 50715. |
a. b. c. Tetrachloroethane does not give the test for unsaturateion , i.e., it does not decolourise Br_(2) water solution. Explain why. d. e. Ricinoleic acid is isolated from castor oil. The structure of the compound is : f.Explain why 1,2-dimethyl cyclopenten or 1,2-dimethyl cyclohexen with HBr undergoes anti-( or trans-) addition but with aqueous acid undergoes both anti- and syn-( trans and cis-) additions. |
Answer» Solution :`a.` `b.`  There are four chiral centrest centres and each of them shows various enentiomers also.  `(F), (G)` and `(H)` have four chiral centres , but `(I)` has only three chiral centres and each of them will show various enantiomers also. `c.`  Because of the `-I` effect of four `Cl` atoms `(i.e.,` electron withdrawing nature of chlorine `)` , the electron density at the double bond is greatly reduced and an attack by electrophilic bromin `(Br^(o+))` does not occur. Hence, it does not show the test for unsaturation. `d.`  `e.` There is ONE `(C=C)` bond with different groups on each `(C=C)` bond and one chiral centre at `C=12` . It shows four geometrical land OPTICAL isomers.  `f.` In non`-` POLAR solvents, the reaction proceeds through a briged cation such as brominimum ion and then `Br^(c-)` attacks the protonated complex from the opposite face resulting in trans `(` anti`-` addition `)`.  In the PRESENCE of aqueous acid, since `H_(2)O` is a good ion sovator, the protonated complex to the free `R^(o+)` that can now react with `Br^(c-)` from either face giving both syn`-` and anti `-` addition.  
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| 50716. |
A,B,C and D are four different gases with critical temperature 304.1,154.3,405.5 and 126.0K respectively. While cooling the gas which gets liquified first is |
| Answer» ANSWER :D | |
| 50717. |
A, B and C are three elements forming part of a compound in oxidation states of +2, +5 and -2 respectively. What could be the compound? |
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Answer» `A_(2)(BC)_(2)` |
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| 50718. |
A ,Band Care elementsin thethirdshortperiod. Oxideof A isionicthat of Bis amphotericand thatof (C )is agiantmolecule . A,Band C will haveatomicnumbers in theorder |
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Answer» `A LT B lt C ` |
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| 50719. |
A, B and C are atoms of elements with atomic number Z, Z+1 and Z+2 respectively. If 'B' has octet configuration, the bond formed between 'A' and C predominently is |
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Answer» COVALENT bond |
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| 50720. |
(A) : Average oxidation number of chlorine in bleaching powder is zero. (R) : Oxidation number of chlorine is always zero. |
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Answer» Both A and R are true and R is the CORRECT EXPLANATION |
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| 50721. |
(a) Assign orientation to the three chlorotoluenes with mu = 1.3, 1.78 and 1.9 D (b) Assign orientation to the three cholornitrobenzenes with mu = 2.5, 3.4 and 4.3 D (c ) Which has higher mu . |
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Answer» SOLUTION :`mu` of (I) GT (III) (i) Bromobenzene (II) is resonance stabillised due to delocalisation of `lp e^(-')s` of the Br ATOM in the benzene ring The `(C -B)` bond acquires some double bond character, while in (I) is a single bond, since it does not undergo resonance In other words, the `(C -Br)` bond in (II) is shorter than that in (ii) Due to more s-character `sp^(2)` hybridised `C` is more `EN` `sp^(3)` hybrid `C` atom, therefore the `sp^(2)` hybrid `C` of the `(C -Br)` bond in (II) has less tendency `C` atom of (I) As a RESULT, the `(C -Br)` bond in (I) is more polar than in (II) i e the magnitude of negative charge (`delta`-) is more on Br atom of (I) than in (II) Therefore `mu` of `(I) gt (II)` [since `mu = q xx d` (charge `xx` distance)]   
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| 50722. |
(A) At 27^(@)C, the kinetic energy of 8 gram of methane is equal to the kinetic energy of 16 gram of oxygen (R) The total heat change in a reaction is the same whether the chemical reaction takes place in one single step or in several steps |
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Answer» If both A and R are CORRECT and R is the correct EXPLANATION of A |
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| 50723. |
Assertion:As_2O_3 and Sb_2O_3 are amphoteric in nature Reason : As and Sb are metalliods |
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Answer» Both (A) and (R) are TRUE and (R) is the CORRECT EXPLANATION of (A) |
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| 50724. |
(a) Arrrange A,B,C and D in order of incresing electrode potential in the electrochemical series if (i) A+B^(+)rarrA^(+)+B,(ii) B +D^(+) rarr B^(+)+D (iii) B+C^(+)rarrB^(+)+C,(iv) C^(+)+Drarr NO reaction (b) on the basisof the above data predict which of the following reaction will ocur (i) A+C^(+) rarrA^(+)+C, (ii) A^(+)+D rarrA+D^(+) |
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Answer» Solution :(a) In the electrochemical SERIES the atoms or species arearranged in ORDER of their decreasing electrode potential (i) since B is reduced by A therefore B has higher electrode potential than A (ii) since D is reduced by B therefore D has higher electrode potential than B (iii) Since C is reduced by B therefore C has higher electrode potential than B (iv) since there is not reaction between `C^(+)` and D i.e C is not reduced by D therefore elecrode potential of the four ELEMENTS decrease in the order `D gt C gt B gt A` (b) (i) since electrode potential of C is higher than that of A therefore `C^(+)` can be easily reduced by A reacton (i) will occur (ii) since electrode potential of D is higher than that of A therefore `A^(+)` cannot be reduced of by D i.e reaction (ii) wil not occur |
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| 50725. |
(A): Aqueous solution of Na_(2)CO_(3) is acidic in nature (R): Na^(+) ion undergoes hydrolysis to produce NaOH and H^(+) ions |
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Answer» Both A and R are TRUE, and R is CORRECT EXPLANATION of A |
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| 50726. |
A aqueous solution of substance on electrolysis gives ethane. The substance is |
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Answer» ACETIC acid |
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| 50727. |
(A): Aq. Na_(2)CO_(32) solution is more basic than that of aq. NaHCO_(3). (R): The extent of hydrolysis of Na_(2)CO_(3) is less than that of NaHCO_(3) |
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Answer» Both A and R are correct and R is the correct explanation of A. |
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| 50728. |
(A) Angular momentum of 1s,2s,3s, etc., all have spherical shape. (R) 1s,2s,3s, etc. all hae spherical shape. |
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Answer» |
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| 50729. |
a and b are van der Waals' constants for gases. Chlorine is more easily liquefied than ethane because |
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Answer» `a " andbfor " Cl_2 GT a " ANDB for " C_2 H_6` |
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| 50730. |
a' and 'b' are van der Waals constants for gases. Chlorine is more easily liquefied than ethane because |
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Answer» a and b for `Cl_(2) lt a` and b for `C_(2)H_(6)` |
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| 50731. |
A and B are two element which form AB_(2) and A_(2)B_(3). If 0.18 mol of AB_(2) weighs 10.6g and 0.18 mol of A_(2)B_(3) weighs 17.8g then - |
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Answer» ATOMIC MASS of A is 20.05 |
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| 50732. |
'A' and 'B' are compounds of sodium. 'A' is thermally stable. On passing CO_(2) through the solution of 'A', 'B' is formed. 'B' on heating gives 'A'. Phenolphthalein is added to the aqueous solution of 'A' and 'B'. The colours of solutions are |
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Answer» Colouress, COLOURLESS |
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| 50733. |
A and B are ideal gases. The molecular weights of A and B are in the ratio of 1 : 4. The pressure of a gas mixture containing equal weights of A and B is P atm. What is the partial pressure (in atm) of B in the mixture? |
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Answer» P/5 |
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| 50734. |
A and B are : |
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Answer» MESO COPOUNDS  Thus A and B are diastereoisomers. |
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| 50735. |
(a) An organic compond A of a moleculer formula C_(3)H_(6), reacts with HBr to give B which is the major product forthis raction. A again reacts with HBr in presence of benzoyl peroxide to give C. Indentify A,B and C. Explain the reactions. |
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Answer» SOLUTION :(a) 1. `CH_(3)-CH=CH_(2)+HBr to underset("2-Bromopropene")(CH_(3)-underset(Br)underset(|)(C)H-CH_(3))` 2. `underset("Propene (A)")(CH_(3)-CH=CH_(2))+HBr overset((C_(6)H_(5)CO)_(2)O)to underset("1-Bromopropene (C)")(CH_(3)-CH_(2)-CH_(2)Br)` 
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| 50736. |
(a) An endothermicreaction A rarr B proceeds to completion . Predict the sign of DeltaS. (b) What will be the sign of DeltaS for the reaction : N_(2)(g) + O_(2)(g) rarr 2NO(g) ? Given reasons in support of your answer. |
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Answer» |
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| 50737. |
(A) : Among IIIA group elements, Boron has highest melting point (R) : Boron has gaint polymeric structure |
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Answer» A and R are TRUE, R explains A |
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| 50738. |
(A): Among Ca^(2+) and Zn^(2+) ions, Ca^(2+) is more stable than Zn^(2+) (R) : Both Ca^(2+) and Zn^(2+) ions are diamagnetic |
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Answer» Both (A) and (R) arc TRUE and (R) is the CORRECT EXPLANATION of (A) |
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| 50739. |
(A): Although phosphorous exhibits +3 and +5 oxidation states, it cannot form PH_5.(R): High Delta Hvalue of dihydrogen do not favour to exhibit the highest oxidation state of phosphorous. The correct answer is |
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Answer» Both A and R are TRUE and R is the CORRECT explanation to A. |
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| 50740. |
(A) All compounds containing an odd number of nitrogen atoms have odd masses and those which contain even number of nitrogen atoms have even masses. (R) Nitrogen rule can be applied to both aliphatic and aromatic compounds. |
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Answer» If both assertion and reason are correct and reason is the correct EXPLANATION of the assertion |
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| 50741. |
(A): Alkenes, carbonyl compounds can exhibit electromeric effect but not alkanes, saturated alcohols (R ): Electromeric effect is possible organic compounds having at least one multiple bond |
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Answer» A and R are true, R explains A |
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| 50742. |
(A) : Alkene is more reactive than the corresponding alkane (R ) : Alkenes contain carbon-carbon double bond |
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Answer» A and R are TRUE, R EXPLAINS A |
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| 50743. |
A alkayl halide with molecular formula C_(6)H_(13)Br on dehydrohalogenation gave two isomeric alkenes X and Y with molecular formula C_(6)H_(12). On reductive ozonolysis, X and Y gave four compounds CH_(3)COCH_(3), CH_(3)CHO, CH_(3)CH_(2)CHO and (CH_(3))_(2) CHCHO. Find the alkyl halide. |
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Answer» Solution :(i) `C_(6)H_(13)BR` is a 3-Bromo-4 METHYLPENTANE.`CH_(3) - UNDERSET(underset(CH_(3))(|))(CH)- underset(underset(H)(|))overset(overset(Br)(|))(C) - CH_(2) - CH_(3)` (ii) 3-Bromo-4 methylpentane on dehydrogenation GIVE two isomers X and Y as follows:  Therefore `C_(6)H_(13)Br` is 3-Bromo-4- methylpentane. |
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| 50744. |
(A) : Alkali metals are very soft and they can be cut with knife (R) : Alkali metals have weak interatomicforces |
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Answer» Both A and R are CORRECT and R is the correct explanation of A . |
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| 50745. |
(A): Alkali metals are not soft and have low melting and boiling points (R): This is because interatomic bonds are weak |
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Answer» Both A and R are CORRECT and R is the correct EXPLANATION of A. |
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| 50746. |
(A) : Alkali metals are good reducing agents (R) : Alkali metals possess high oxidation potentials |
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Answer» Both A and R are TRUE, and R is CORRECT EXPLANATION of A |
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| 50747. |
(A) Acid rains have been reported in some places which are far away from the places where industries are located (B) (R) : Rain coluds move away from industries. |
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Answer» Both (A) and (R) are TRUE and (R) is the CORRECT EXPLANATION of (A) |
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| 50748. |
(A) : Acetylene is used in oxyacetylene flame (R ) : The heat of combustion of acetylene is more than that of ethane or ethylene |
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Answer» A and R are true, R EXPLAINS A |
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| 50749. |
(A) : Acetylene reacts with ammonical cuprous chloride to form red precipitate (R ) : Hydrogen atom bonded to sp hybridised carbon atom is acidic in nature. |
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Answer» A and R are true, R EXPLAINS A |
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| 50750. |
(a) Account for the acidity of alkynes. (b) Explain the mechanism of sulphonation of benzene. ( c ) How will you convert the following : (i) Ethyne to but-2-yne(ii) Propeneto 2, 3-dimethylbutane(iii) Etheneto ethyne. |
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Answer» Solution :( c ) (i)`underset("Ethyne")(HC-=CH)overset(2NaNH_(2))toNaC-=CNa overset(2CH_(3)Br)toCH_(3)underset("But-2-yne")(C-="CCH"(3))` (ii) `underset("Propene")(CH_(3)CH=)CH_(2)overset(HBr)toCH_(3)underset(Br)underset(|)(C)HCH_(3)overset("Na, ETHER")underset("WURTZ REACTION")to underset("2,3-Dimethyl butane")(CH_(3)underset(CH_(3))underset(|)(C)H-underset(CH_(3))underset(|)(C)H-CH_(3))` (iii) `underset("Ethene")(CH_(2)=CH_(2))overset(Br_(2),"CCl"_(4))tounderset(Br)underset(|)(C)H_(2)-underset(Br)underset(|)(C)H_(2)overset("2 alc. KOH")tounderset("Ethyne")(HC-=CH)` |
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