Basic Concepts of ChemistryPhysical and Chemical Changes16Choose the best answerWhich of the following is an example of a chemical change?AMelting of iceBSwitching on a bulbCCutting fruit into piecesDRusting of iron Like 0 Discuss 0Share
Basic Concepts of ChemistryPhysical and Chemical Changes17Choose the best answerWhich of the following is not a chemical change?APhotosynthesisBDigestionCTearing a paperDRusting of iron Like 0 Discuss 0Share
Basic Concepts of ChemistryElements, Compounds and Mixtures18Choose the best answerWhich of the following contains only one element?AMarbleBDiamondCGlassDSand Like 0 Discuss 0Share
Basic Concepts of ChemistryElements, Compounds and Mixtures19Choose the best answerWhich one of the following is not an element?ADiamondBGraphiteCSilicaDOzone Like 0 Discuss 0Share
Basic Concepts of ChemistryElements, Compounds and Mixtures20Choose the best answerAn element cannot:ABe present in a heterogeneous mixtureBBe present in a homogeneous mixtureCBe decomposed into simpler substances by ordinary chemical meansDCombine with another element to form a compound Like 0 Discuss 0Share