Consider the following statements:<br>1. Packaged foods are purged with nitrogen gas in order to prevent their oxidation.<br>2. Tooth decay starts when pH of the mouth is lower than 5.5.<br>3. The reactivity of metals decreases in the order: Mg \gt Fe \gt Zn.<br>Which of the statements given above is/are <strong>NOT</strong> correct?

  1. A. 2 and 3
  2. B. 1 and 3
  3. C. 1 and 2
  4. D. 3 only

Correct Answer: D. 3 only

Explanation

Statement 3 is incorrect because the correct reactivity series order for these metals is Magnesium > Zinc > Iron (Mg \gt Zn \gt Fe). Statements 1 and 2 are scientifically correct.

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