Q31.Complete combustion of 1. 80 g of an oxygen containing compound (CxHyOz) gave 2. 64 g of CO2 and 1. 08 g of H2O. The percentage of oxygen in the organic compound is : (1) 53. 33 (2) 50. 33 (3) 51. 63 (4) 63. 53
What This Question Tests
This question is hard as it implies a scenario where the same size image is formed at two different object distances, which is not typically possible with a single real object for a convex lens unless 'same size' is interpreted as 'same magnitude of magnification' (one real, one virtual) or there's an ambiguity in the wording of the question regarding real/virtual image or object. If it means 'same magnitude of magnification', it still requires careful analysis of the lens formula.
Concepts Tested
Formulas Used
1/f = 1/v - 1/u
m = v/u
📚 NCERT Sections This Tests
1.28 — Calculate The Mass Percentage Of Aspirin (C9H8O4) In Acetonitrile (Ch3Cn) When
Chemistry Class 11 · Chapter 1
1.28 Calculate the mass percentage of aspirin (C9H8O4) in acetonitrile (CH3CN) when 6.5 g of C9H8O4 is dissolved in 450 g of CH3CN.
8.19 — An Organic Compound Contains 69.77% Carbon, 11.63% Hydrogen And Rest Oxygen.
Chemistry Class 12 · Chapter 8
8.19 An organic compound contains 69.77% carbon, 11.63% hydrogen and rest oxygen. The molecular mass of the compound is 86. It does not reduce Tollens’ reagent but forms an addition compound with sodium hydrogensulphite and give positive iodoform test. On vigorous oxidation it gives ethanoic and propanoic acid. Write the possible structure of the compound.
1.3 — Define The Following Terms:
Chemistry Class 11 · Chapter 1
1.3 Define the following terms: (i) Mole fraction (ii) Molality (iii) Molarity (iv) Mass percentage.
📋 Question Details
- Chapter
- Ray Optics
- Topic
- Lens formula, Image formation
- Year
- 2021
- Shift
- 25 Feb Shift 1
- Q Number
- Q31
- Type
- Numerical
- NCERT Ref
- Class 12 Physics Ch 9: Ray Optics and Optical Instruments
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