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Q. 2. Name the compound formed when ethanol is warmed with ethanoic acid in the presence of a few drops of conc. H₂SO₄. 1

Ans. When ethanol is warmed with ethanoic acid in the presence of a few drops of conc. H₂SO₄, a sweet smelling ester, ethyl ethanoate is formed.

Q. 3. Lithium, sodium and potassium form a Dobereiner’s triad. The atomic masses of lithium and potassium are 7 and 39 respectively. Predict the atomic mass of sodium. 1

Ans. The atomic mass of sodium is the arithmetic mean of the masses of lithium and potassium.

Q. 4. Redraw the diagram given in your answer book and show the direction of the light ray after reflection from the mirror. 1

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Ans.

Science 2009 Question Papers Class X
Delhi		Outside Delhi		Compartment Delhi		Outside Delhi		Foreign
	Set 1 (PDF)		Set 1 (PDF)		Set 1		Set 1		Set 1 (PDF)
					Set 2		Set 2
					Set 3		Set 3