Question
In which of the following years did Antoine Lavoisier
discover the law of conservation of mass?Solution
Antoine Lavoisier discovered the law of conservation of mass in 1789. The law states that mass is neither created nor destroyed in a chemical reaction. It laid the foundation for modern chemistry and explained the concept of closed systems in reactions. Key Points: 1. Lavoisier is known as the "Father of Modern Chemistry." 2. His work on combustion helped explain the role of oxygen in chemical reactions. 3. The conservation of mass law applies universally to all chemical processes. 4. It formed the basis for stoichiometry in chemistry. 5. He was instrumental in developing a systematic chemical nomenclature. Bee Facts: • 1783 (a): Incorrect; Lavoisier’s early works started in this period. • 1785 (b): Incorrect; related to experiments on combustion. • 1789 (c): Correct, year of publishing his work. • 1792 (d): Incorrect; Lavoisier was involved in political activities by then.
122, 116, 125, 119, 128, ?
Select the number from among the given options that can replace the question mark (?) in the following series.
8, 27, 64, 125, 216, ?
6, 17, 21, 47, ?, 107
75    196    52    221    ?    250
2, A, 9, B, 6, C, 13, D, ?
100, 110, ?, 171.6, 240.24, 360.36
5Â Â Â Â 13Â Â Â Â 36Â Â Â Â 145Â Â Â Â Â 719Â Â Â Â 4321
9Â Â Â 4.5Â Â Â 4.5Â Â Â 9Â Â Â 36Â Â Â ?
5 ? 205 823 7405 29623
D irection: Which of the following will replace ‘?’ in the following series
10,14,’?’,199, 352, 530
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