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.
| 1. |
The element with atomic number 17 has the least size among all the elements of that period |
| Answer» Correct Answer - true | |
| 2. |
The elctorn affinity increases on moving form left to right along a period .Arrange the reason in a proper sequenceA. 1324B. 3241C. 3142D. 4321 |
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Answer» Answer: (i)The atomic size the elements decrease from left to right (ii) Efective nuclear charge of the elements increase from left to right (iii) The tendency to gain electrons and form anoons increase form left to right (iv) The amount of energy released during the addition of an electron increases form left to right along periods |
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| 3. |
Which among the following pairs of elements have maximum and minimum electron affinity values respectively?A. Be,CIB. He,LKC. Be,SD. CI,Cs |
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Answer» Answer: Insert gases have zero electon affinity due to their stable octet configurtion whereas IA group elements have minimum electron affinity value due to large atomic size halogens have high electron affinity due to small atomic size hence ci and cs have maximum and minimum electron affinity values respectively |
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| 4. |
X nelongs ot IA or first rop and fifth period and y succeeds X in the group .Z succeeds Y in the period Arrange the suitable statement in the correct sequence in order ot arrnge X,Y and Z in the incresing order of their atomic sizesA. dbcaB. bdcaC. cadD. dca |
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Answer» Answer: (i) Determination of the positons of y and z in the peroidc table based opn the position of x (ii) Determination of the number of shells and the number of valence elctrons present in x y and z (iii) Efect of the number of valence electrons and number of shells on atomic size |
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| 5. |
Element X has 12 neutorns in its nucleous .To which group in the periodic table would it belongs?A. 1B. 2C. 3D. cannot be predicated |
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Answer» Answer: The postion of the element in the peroodic table connot be predicted based on the number of neiutrons present in the nucleus |
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| 6. |
The formula of iron formed by and element A is `A^(2+)` The element A can probly belong to which of the following groups?A. IIIAB. VIIAC. IIAD. IA |
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Answer» Answer: The formula of ion formed by A is `A^(2+)` `rarr`valency of A is 2 `therefore` A belong to II A group |
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| 7. |
The element which accepts electrons readily to form anion belongs toA. VII A group and second periodB. VII A group and third periodC. O group and third periodD. VI A group and third period |
| Answer» Correct Answer - b | |
| 8. |
The chemistry of alkali metals is essentially the chemitry of unipositive ions becasuseA. they have low ionisation energy valuesB. they have strong tendency to lose single valence electronC. second ionidatin energy values are very highD. all the above |
| Answer» Correct Answer - d | |
| 9. |
`Na^(+),F^(-)` and `Mg^(+2)` ions have the sameA. sizeB. electronic configurationC. ionisation energyD. nuclear charge |
| Answer» Correct Answer - b | |
| 10. |
Galliu is more electronegative of the elements decrease down the group .It is due to ______A. increase in the atomic sizeB. increase in the ionisation energyC. increase of effective nuclear chargeD. all the above |
| Answer» Correct Answer - c | |
| 11. |
The total number of inner transition elements is __________A. 14B. 28C. 20D. 15 |
| Answer» Correct Answer - b | |
| 12. |
Identify the oxide which forms the strongest base:A. MgOB. `AI_(2)O_(3)`C. `Na_(2)O`D. `CaO` |
| Answer» Correct Answer - c | |
| 13. |
Is the triangle with sides 14cm, 12cm and 17cm a right triangle? Why? |
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Answer» No, it is not a right angle triangle. Explanation: As we know, in a right-angled triangle the hypotenuse is the longest side. Of all the three sides given here, 17cm must be hypotenuse. According to Pythagoras theorem, (Hypotenuse)2 = (other side1)2 + (other side 2)2 |
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| 14. |
निम्न व्यंजकों के गुणनखण्ड ज्ञात कीजिए(i) x3 + 64(ii) 1 – 125y3(iii) \(\frac{p^{3}}{343}\) + 8q3(iv) 7m4n – 7mn4(v) x7y7 – xy |
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Answer» (i) x3 + 64 = (x)3 + (4)3 = (x + 4)(x2 + 16 – 4x) (ii) 1-125y3 = (1)3 – (5y)3 = (1 – 5y)(1 + 25y2 + 5y) (iii) \(\frac{p^{3}}{343}+8 q^{3}=\left(\frac{p}{7}\right)^{3}+(2 q)^{3}\) \(=\left(\frac{p}{7}+2 q\right)\left(\frac{p^{2}}{49}+4 q^{2}-\frac{2}{7} p q\right)\) (iv) 7m4n – 7mn4 = 7mn(m3 – n3) = 7mn[(m)3– (n)3] = 7mn[(m – n)(m2 + n2 + mn)] (v) x7y7 – xy = xy(x6y6 – 1) = xy[(x2y2)3 – (1)3] = y[(x2y2 – 1)(x4y4 + 1 + x2y2] = xy [(xy)2 – (1)2) (x4y4 – 1 + 2x2y2 xy2)] = xy (xy + 1)(xy – 1)[(x2y2 + 1)2 – (xy)2] = xy(xy + 1)(xy – 1)(x2y2 + 1 + xy)(x2y2 + 1 – xy) |
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| 15. |
Which of the following belong to the same group? `A^(3+)` (number of electrons=10) `B^(2+)`(number of electrons =10) C (number of electorns =5) D (number of electorns=31)A. abcB. bcdC. acdD. adb |
| Answer» Correct Answer - c | |
| 16. |
Which of the following is a compound ?A. steelB. brassC. iron sulphideD. iodine |
| Answer» Correct Answer - C | |
| 17. |
Which of the following is a chemical change ?A. mixitng of iron filings and sandB. freezing of waterC. passage of electricity through wiresD. fermentation of grapes |
| Answer» Correct Answer - D | |
| 18. |
Which of the following is not an element ?A. oxygenB. bromineC. paperD. zinc |
| Answer» Correct Answer - C | |
| 19. |
Which of the following is an element ?A. marbleB. graphiteC. washingD. soda |
| Answer» Correct Answer - B | |
| 20. |
Which of the following is expected to show tyndall effect ?A. a solution of common saltB. milkC. a solution of sodium carbonateD. starch solution |
| Answer» Correct Answer - D | |
| 21. |
Does an element contain atoms of the same kind ? |
| Answer» Yes, but when isotopes are not present . | |
| 22. |
Which of the following represents an element ?A. brassB. stainless stellC. arsenicD. silica |
| Answer» Correct Answer - C | |
| 23. |
Which one of the following mixtures is a solution ?A. soilB. sea waterC. airD. soda water |
| Answer» Correct Answer - B | |
| 24. |
A sample (A) of water boils at `100^@C` whereas another same (B) of water boils at `101.2^(@)C` . Identify the sample which will not freeze at ` 0^@C` . |
| Answer» Sample (B) will not freeze at ` 0^(@)C` as it contains some impurity . | |
| 25. |
Which of the following represents a solid liquid mixture ?A. a mixture of sugar and sandB. airC. air trapped in soil particvlesD. a solution of common salt in water |
| Answer» Correct Answer - D | |
| 26. |
Which of the following is not a compound ?A. Dry iceB. PotashC. IodineD. Alumina |
| Answer» Correct Answer - C | |
| 27. |
Calculate the concentration of a solution in volume per cent made when 56 g water is mixed with 0.17 L of ethanol |
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Answer» Volume of water `=("mass")/("density")=(56 g)/(1.0 g cm^(-3))=56 cm^(3)=56` mL volume of ethanol `=0.17 xx1000 mL = 170 mL` `therefore` concentration per cent by volume =`(56)/(226)xx100=24.78%` |
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| 28. |
Which of the following statements about the formation of a compound is ( are ) correct ?A. A compound contains only one kind of element .B. During the formation of a compound heat energy change may or may not occur .C. A compound has a sharp melting point .D. A compound is a homogeneous substance. |
| Answer» Correct Answer - C::D | |
| 29. |
Light will get scattered when a beam light is allowed to pass throughA. an aqueous solution of ureaB. an aqueous solution of `CuSO_(4)`C. distilled waterD. blood |
| Answer» Correct Answer - D | |
| 30. |
Two substances A and B combine together to produce a new substance C. The properties of C do not tally with those of A and B. A and B cannot be separted into simpler substance by any chemical means . Which of the following statements is ( are ) correct about the formation of C?A. A and B are elements.B. A and B are compounds.C. C is a mixture of A and B.D. A and B are present in C in a fixed ratio by mass. |
| Answer» Correct Answer - A::D | |
| 31. |
20 `cm^(3)` of an alcohol is dissoved in 80 `cm^(3)` of water calculate the percentage of alcohol in the solution |
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Answer» Volume of alcohol = 20 `cm^(3)` Volume of water = 80 `cm^(3)` `therefore` percentage of alcohol =`(20)/(20+80)xx100=20` |
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| 32. |
What is the volume pecent of a solution prepared by dissolving 15 `cm^(3)` of methanol in `100 cm^(3)` of ethanol? |
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Answer» Volume of methanol = `15 cm^(3)` Volume of ethanol = `100 cm^(3)` `therefore` volume of the solution `= (15+100)=115 cm^(3)` `therefore` volume per cent of solution = `(15)/(115)xx100=13.04%` |
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| 33. |
A student was aked a prepare a 20% ( volume by volume ) solution of ehtanol in water . How should the student do it ? |
| Answer» 20mL ethanol + 80mL water | |
| 34. |
Write a program in Python to explain logical operators. |
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Answer» Following example to understand all the logical operators available in Python programming language: #!/usr/b in/python a = 10 b = 20 c = 0 if (a and b): print “Line 1 – a and b are true” else: print “Line 1 – Either a is not true or b is not true” if (a or b): print “Line 2 – Either a is true or b is true or both are true” else: print “Line 2 – Neither a is true nor b is true” a = 0 if ( a and b ): print “Line 3 – a and b are true” else: print “Line 3 – Either a is not true or b is not true” if ( a or b ): print “Line 4 – Either a is true or b is true or both are true” else: print “Line 4 – Neither a is true nor b is true” if not( a and b) : print “Line 5 – a and b are true” else: print “Line 5 – Either a is not true or b is not true” When you execute the above program it produces following result: Line 1 – a and b are true Line 2 – Either a is true or b is true or both are true Line 3 – Either a is not true or b is not true Line 4 – Either a is true or b is true or both are true Line 5 – a and b are true |
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