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Zorluk: ZorChemistry in Daily Life and Industrial Applications

With reference to chemicals widely used in daily life and food processing, consider the following statements:

1. Sodium benzoate functions as an effective food preservative primarily in acidic conditions by inhibiting microbial growth.
2. Calcium carbide (CaC2CaC_2) releases ethylene gas (C2H4C_2H_4) upon reaction with moisture to artificially ripen fruits.
3. Aspartame decomposes at elevated cooking temperatures, making its use restricted to cold foods and soft drinks.

Which of the statements given above is/are correct?

  1. A
    1 and 2 only
  2. 1 and 3 onlyCevap
  3. C
    2 and 3 only
  4. D
    1, 2 and 3

Cevap

Statements 1 and 3 only are correct.
The correct response identifies that statements 1 and 3 are factually accurate. Sodium benzoate operates effectively as a antimicrobial preservative in acidic mediums (pH < 4.5) like soft drinks and pickles. Aspartame decomposes under heat and is strictly used in cold food items. Statement 2 is false because calcium carbide reacts with water to yield acetylene gas (C2H2C_2H_2), not ethylene gas (C2H4C_2H_4).

Adım Adım Çözüm

1
Analyze statement 1 regarding Sodium benzoate
Sodium benzoate (C6H5COONaC_6H_5COONa) is converted to benzoic acid in low pH (acidic) environments, which penetrates microbial cells and inhibits cellular enzymes. Statement 1 is correct.
Verify the mechanism and optimal pH conditions for sodium benzoate as a food preservative.
2
Analyze statement 2 regarding Calcium carbide
Calcium carbide (CaC2CaC_2) reacts with atmospheric moisture to produce acetylene gas (C2H2C_2H_2), according to the reaction CaC2+2H2O→Ca(OH)2+C2H2CaC_2 + 2H_2O \rightarrow Ca(OH)_2 + C_2H_2. Acetylene mimics ethylene in ripening, but the gas produced directly is acetylene, not ethylene. Statement 2 is incorrect.
Identify the precise chemical gas liberated by calcium carbide during fruit ripening.
3
Analyze statement 3 regarding Aspartame
Aspartame is a methyl ester of a dipeptide (aspartic acid/phenylalanine). It breaks down at high temperatures, losing its sweet flavor. Thus, it is unsuitable for baking or hot cooking. Statement 3 is correct.
Check thermal stability and culinary applications of artificial sweeteners.

Anahtar Kavram

Chemical compounds in food preservation, artificial ripening, and non-nutritive sweeteners
Tahmini Süre:1m 30s
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Konular

Chemistry in Daily Life and Industrial Applications

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