MCQ 11 MarkFatty foods become rancid due to the process of $–$✓OxidationBCorrosionCreductionDhydrogenationAnswerCorrect option: A. OxidationView full question & answer→
MCQ 21 MarkBoth CO2 and H2 gases are –A Heavier than air✓ ColourlessCAcidic in natureD soluble in waterAnswerCorrect option: B. Colourless ColourlessView full question & answer→
MCQ 31 MarkChemically rust is $–$AHydrated ferrousBOnly ferric oxide✓Hydrated ferric oxideDNone of theseAnswerCorrect option: C. Hydrated ferric oxideView full question & answer→
MCQ 41 MarkOn immersing an iron nail in CuSO4 solution for few minutes, you will observe –ANo reaction takes placeB The colours of solution fades awayCThe surface of iron nails acquire a black coating✓The colour of solution changes to greenAnswerCorrect option: D. The colour of solution changes to greenthe colour of solution changes to greenView full question & answer→
MCQ 51 MarkThe reaction of H2 gas with oxygen gas to form water is an example of –✓ CombinationBRedox reactionC Exothermic reactionDAll of theseAnswerCorrect option: A. CombinationCombinationView full question & answer→
MCQ 61 MarkRancidity can be prevented by $–$AAdding antioxidantsBStoring food away from lightCKeeping food in refrigerator✓All of theseAnswerCorrect option: D. All of theseView full question & answer→
MCQ 71 MarkWhen a magnesium ribbon is burnt in air, the ash formed is –ABlack✓ WhiteC YellowD PinkAnswerCorrect option: B. White WhiteView full question & answer→
MCQ 81 MarkWhen carbon dioxide is passed through lime water –ACalcium hydroxide is formedB White precipitate of CaO is formed✓ Lime water turns milkyDColour of lime water disappearsAnswerCorrect option: C. Lime water turns milkylime water turns milkyView full question & answer→
MCQ 91 MarkDissolved gases like sulphur dioxide and nitrogen oxides in rain water causes ________.Aacid rainBbase rainCheavy rainDneutral rainAnswerDissolved gases like sulphur dioxide and nitrogen oxides in rain water causes acid rain.View full question & answer→
MCQ 101 MarkIn Haber’s process of producing ammonia _______ is used as a catalyst.AnitrogenBhydrogenCironDnickelAnswerIn Haber’s process of producing ammonia, iron is used as a catalyst.View full question & answer→
MCQ 111 MarkWhich of the following factor induces electrtolysis?AHeatBLightCElectricityDCatalysisAnswerElectricityView full question & answer→
MCQ 121 MarkLimestone contains ______ mainly.Acalcium chlorideBCalcium carbonateCcalcium nitrateDcalcium sulphateAnswerLimestone contains Calcium carbonate mainly.View full question & answer→
MCQ 131 MarkBrine is a concentrated solution of ______.Asodium sulphateBsodium chlorideCcalcium chlorideDsodium bromideAnswerBrine is a concentrated solution of sodium chloride.View full question & answer→
MCQ 141 MarkThe pigment responsible for browning of apples is ______.Ahydrated iron (II) oxideBmelaninCstarchDozoneAnswerThe pigment responsible for browning of apples is melanin.View full question & answer→
MCQ 151 Mark_______ undergoes rusting.ATinBSodiumCCopperDIronAnswerIron undergoes rusting.View full question & answer→
MCQ 161 MarkBurning of matchstick is an example for chemical reaction caused by _______Acontact in physical statesBelectricityClightDcatalystAnswerBurning of matchstick is an example for chemical reaction caused by light.View full question & answer→
MCQ 171 MarkBurning of paper is a ______ change.AphysicalBchemicalCphysical and chemicalDneutralAnswerBurning of paper is a chemical change.View full question & answer→
MCQ 181 Mark_______ is/are responsible for global warming.ACarbon dioxideBMethaneCChlorofluorocarbonsDCarbon dioxide, Methane, ChlorofluorocarbonsAnswerCarbon dioxide is/are responsible for global warming.View full question & answer→