MCQ 11 MarkWhat is the atomic number of an element whose electronic configuration is 2, 8, 1?A10B23✓11D8AnswerCorrect option: C. 1111View full question & answer→
MCQ 21 MarkAn atom differs from its ion in ………………A nuclear chargeB mass number✓ number of electronsDnumber of protonsAnswerCorrect option: C. number of electronsnumber of electronsView full question & answer→
MCQ 31 MarkIsotopes exist because atoms of the same element can have different numbers of –A protons✓ neutronsC electronsDnoneAnswerCorrect option: B. neutronsneutronsView full question & answer→
MCQ 41 MarkMetals form ……………..A anions✓ cationsC both a and bDnoneAnswerCorrect option: B. cationscationsView full question & answer→
MCQ 51 MarkWhatis the valency of carbon?A1B2C3✓4AnswerCorrect option: D. 44View full question & answer→
MCQ 61 MarkThe equation $Na + H _2 O \rightarrow NaOH + H _2$ is ………………Acorrect✓incorrect since it is not balancedCincorrect since hydrogen should be written as H and not $H_2$DNoneAnswerCorrect option: B. incorrect since it is not balancedincorrect since it is not balancedView full question & answer→
MCQ 71 MarkThe valency of which of the element is zero.A ironB hydrogen✓ heliumDoxygenAnswerCorrect option: C. heliumheliumView full question & answer→
MCQ 81 MarkThe outer most shell of an atom is known as ………………..A valencyB valence electronC nucleus✓valance shellAnswerCorrect option: D. valance shellvalance shellView full question & answer→
MCQ 91 MarkWhich of the following scientists observed that cathode rays consists of negatively charged particles?A John Dalton✓ J.J. ThomsonC James ChadwickDDemocritusAnswerCorrect option: B. J.J. ThomsonJ.J. ThomsonView full question & answer→
MCQ 101 MarkIn all atoms of an elementAthe atomic and the mass number are same.Bthe mass number is same and the atomic number is different.Cthe atomic number is same and the mass number is differentDboth atomic and mass numbers may varyAnswerThe atomic and the mass number are same.View full question & answer→
MCQ 111 MarkWhich of the following statements made by Dalton has not undergone any change?AAtoms cannot be broken.BAtoms combine in small, whole numbers to form compounds.CElements are made up of atoms.DAll atoms of an elements are alikeAnswerAll atoms of an elements are alike.View full question & answer→
MCQ 121 MarkIn water, hydrogen and oxygen are combined in the ratio of _____ by mass.A$1:8$B$8:1$C$2:3$D$1:3$Answer$1:8$ View full question & answer→
MCQ 131 MarkCathode rays are made up ofAneutral particlesBpositively charged particlesCnegatively charged particlesDNone of the aboveAnswerNegatively charged particlesView full question & answer→
MCQ 141 MarkThe same proportion of carbon and oxygen in the carbon dioxide obtained from different sources proves the law of ______.Areciprocal proportionBdefinite proportionCmultiple proportionDconservation of massAnswerdefinite proportion.View full question & answer→