Question Detail Who proposed first atomic theory ? E.RutherfordDe BroglieJohn DaltonD.I.Mendeleef Answer: Option C Ad Similar Questions : 1. What is used to avoid melting of ice ? GelatineButaneMethaneAny acid Answer: Option A 2. Enzymes are Fatty acidsCarbohydratesNucleic acidsProteins Answer: Option D 3. Which acid is present in lemon ? marlic acidcitric acidlactic acidtartaric acid Answer: Option BExplanation:citric acid is present in lemon. 4. Air is a compoundcolloidelementmixture Answer: Option D 5. The ejection of electrons when a metal surface is irradiated is known as Black body radiationPhotoelectric effectZeeman effectAtomic spectrum Answer: Option B Read more from - Chemistry Questions Answers