CH#1     Basic Concept

1.	Diameter of an atom is in the order of
	A. 0.2m B. 0.2mm C. 0.2nm D. 0.2pm

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2.	Which of the following are isoelectronic species?
	A. H+ H H- B. Li+ Na+ K+ C. C1- Br- I D. F- Ne Na+

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3.	Mass spectrometer is used to determine Mass number of isotopes and
	A. Atomic number B. Relative abundance C. Electronic configuration D. All of the above

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4.	Molecular ions are formed by passing
	A. High energy electron beam B. ? - particle C. X-rays D. All of the above

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5.	The number of peaks obtained in mass spectrometry shows
	A. Relative abundance B. Average mass of element C. Number of isotopes D. Relative isotopic mass

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6.	Empirical formula of chloroform is
	A. CH2 C12 B. CH3C1 C. CC14 D. CHC13

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7.	Which one is true about isotope?
	A. Same number of neutrons B. Same mass number C. Same physical properties D. Same chemical properties

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8.	Molecular mass of water (18g) means
	A. 1-mole molecules of water B. 1-gram molecule of water C. 3-gram atoms D. all

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9.	Which of the following ion formation is always exothermic?
	A. Uni-negative B. Uni-positive C. Di-negative D. Di-positive

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10.	Which of the following statements about isotopes is correct?
	A. Isotopes with odd atomic number are abundant B. Isotopes with odd atomic number and even mass number are abundant C. Isotopes with even atomic number and even mass number are abundant D. Isotopes with even atomic number and odd mass no are abundant

11.	The sample of isotopes of an element which needs not to be vaporized in the vaporization chamer
	A. Gas B. Liquid C. Volatile solid D. All

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12.	One mole of CO2 contains.
	A. 6.022 x 1023 atoms of oxygen B. 22-gram electrons C. 6.022 x 1023 atoms of carbon D. both b & c

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13.	Avogadro’s number may represent
	A. volume of particles B. number of particles C. mass of particles D. All of the above

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14.	The number of isotopes of elements with even mass number and even atomic number are.
	A. 280 B. 300 C. 154 D. 54

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15.	Size of molecule depends upon
	A. Atomicity B. Shape of molecule C. Both a and b D. Difficult to predict

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16.	Which of the following terms is not used for ionic compound?
	A. formula unit B. empirical formula C. molecular formula D. formula mass

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17.	0.36 moles of each aluminum and oxygen react with each other to produce aluminum oxide. The amount of product formed is
	A. 0.18 mole B. 0.27 mole C. 0.24 mole D. 0.09 mole

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18.	Which of the following terms is used for the mass of chlorine 35.5?
	A. relative atomic mass B. mass number C. atomic weight D. relative isotopic mass

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19.	Which one of the following has the maximum number of isotopes?
	A. oxygen B. carbon C. tin D. chlorine

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20.	Which one of the following is not the mono isotopic element?
	A. arsenic B. uranium C. iodine D. nickel
21.	The volume occupied by 2.8 g of N2 at STP
	A. 2.24 dm3 B. 22.4 dm3 C. 1.12 dm3 D. 112 dm3

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22.	The mass of decimal of electrons (NA) is
	A. 1.008 mg B. 0.184 mg C. 0.054 mg D. 5.4 mg

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23.	The number of moles of CO2 which contains 16 g of oxygen is
	A. 0.25 B. 0.5 C. 0.75 D. 1

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24.	Which of the following statements is wrong about isotopes?
	A. they possess different mass number B. they possess different physical properties C. they possess same chemical properties D. they possess different position in the periodic table

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25.	How many isotopes have odd atomic number?
	A. 154 B. 280 C. 86 D. 300

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26.	Qualitative analysis is carried out for
	A. identification of elements B. estimation of amounts of elements C. molar ration of elements D. molar volume of elements

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27.	Percentage of calcium in calcium carbonate is
	A. 80% B. 30% C. 40% D. 20%

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28.	Combustion analysis is performed to determine
	A. Empirical formula B. Molecular mass C. Molecular formula D. Formula mass

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29.	Mostly elements have fractional atomic masses because of
	A. mass of an atom itself is in fraction B. atomic masses are average masses of isobars C. atomic masses are average masses of isotopes proportional to their relative abundance D. atomic masses are average masses of isotopes

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30.	Isotopes differ in
	A. properties which depend upon mass B. arrangement of electrons in orbitals C. chemical properties D. all of the above
31.	Which of the following is not a macromolecule?
	A. sand B. hemoglobin C. diamond D. maltose

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32.	Which of the following methods is used to estimate hydrogen in an organic compound?
	A. Combustion method B. Dumas method C. Kjeldahls method D. All of the above methods are for different purposes

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33.	Isotopes of the same elements has
	A. different number of protons B. same number of neutrons C. different number of neutrons D. same mass number (nucleon number)

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34.	The nucleus of an atom of every element will always contain
	A. neutrons B. protons and electrons C. protons D. protons and neutrons

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35.	When cationic molecular ions are allowed to pass through strong magnetic field in mass spectrometer which of the following ions is fallen
	A. lighter B. intermediate C. heavier D. are collected at same time

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36.	When 0.5 mole of phosphoric acid is dissolved in aqueous solution how many moles of -ve and +ve ions are collected altogether?
	A. 0.5 B. 1 C. 1.5 D. 2

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37.	For which of the following compounds the term empirical formula cannot be applied?
	A. NaCl B. H2O C. CCI4 D. It can be applied to all mentioned above

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38.	Dumpsters mass spectrometer has number of zones / parts
	A. 5 B. 4 C. 3 D. 2

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39.	The properties of an element mostly corresponds to that isotope which has greater
	A. Mass number B. Atomic mass C. Relative abundance D. all of the above

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40.	1 a.m.u =
	A. 1.6 x 10-27 kg B. 1.6 x 10-24 kg C. 1.6 x 10-26 kg D. 1.6 x 10-28 kg

Answers

	1.     C	2.     D	3.     B	4.     D	5.     C	6.     D	7.     D	8.     D	9.     A
10.                        C	11.                        A	12.                        D	13.                        D	14.                        C	15.                        C	16.                        C	17.                        A	18.                        A	19.                        C
20.                        B	21.                        A	22.                        C	23.                        B	24.                        D	25.                        C	26.                        A	27.                        C	28.                        A	29.                        C
30.                        A	31.                        D	32.                        A	33.                        C	34.                        C	35.                        A	36.                        D	37.                        D	38.                        A	39.                        C
40.                        A