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Give two reasons for the appearance of variations among the progeny formed by sexual reproduction.
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How are power and focal length of a lens related? You are provided with two lenses of focal length 20 cm and 40 cm respectively. Which lens will you use to obtain more convergent light?
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Anita added a drop each of diluted acetic acid and diluted hydrochloric acid on pH paper and compared the colors. Which of the following is the correct conclusion?
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Shristi heated Ethanol with a compound A in presence of a few drops of concentrated sulphuric acid and observed a sweet smelling compound B is formed. When B is treated with sodium hydroxide it gives back Ethanol and a compound C.
- Identify A and C
- Give one use each of compounds A and B.
- Write the chemical reactions involved and name the reactions.
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Reshu by mistake forgot to label the two test tubes containing Ethanol and Ethanoic acid. Suggest an experiment to identify the substances correctly? Illustrate the reactions with the help of chemical equations.
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Assertion (A): Testes in human males are located outside the abdominal cavity in scrotum.
Reason (R): Scrotum provides a lower temperature than the normal body temperature for sperm formation.
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An object of height 10 cm is placed 25 cm away from the optical centre of a converging lens of focal length 15 cm. Calculate the image distance and height of the image formed.
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What happens when a small piece of sodium is dropped in ethanol? Write the equation for this reaction.
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Why is glacial acetic acid called so?
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Write an equation showing saponification.
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Write the chemical equation for the following:
Esterification Reaction
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Write the chemical equation for the following:
Saponification Reaction
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Raina while doing certain reactions observed that heating of substance ‘X’ with a vinegar-like smell with a substance ‘Y’ (which is used as an industrial solvent.) in the presence of conc. Sulphuric acid in a water bath gives a sweet-smelling liquid ‘Z’ having molecular formula C4H8O2. When heated with caustic soda (NaOH), ‘Z’ gives back the sodium salt and the compound ‘Y’.
Identify ‘X’, ‘Y’, and ‘Z’. Illustrate the changes with the help of suitable chemical equations.
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Given below is a certain situation. Analyze and describe its possible impact on a person:
Testes of a male boy are not able to descend into the scrotum during his embryonic development.
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Given below is a certain situation. Analyze and describe its possible impact on a person:
The Vas deferens of a man is plugged.
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Given below is a certain situation. Analyze and describe its possible impact on a person:
Prostate and seminal vesicles are not functional.
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A spatula full of sodium carbonate is taken in a test tube and 2 mL of dilute ethanoic acid is added to it.
Write a chemical equation for the reaction.
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A spatula full of sodium carbonate is taken in a test tube and 2 mL of dilute ethanoic acid is added to it.
Suggest a method of testing the gas liberated in the reaction.
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Name the oxidising agent used in the conversion of ethanol to ethanoic acid.
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Write the chemical equation for the ethanol to ethanoic acid of an oxidation reaction.
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