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Q. Which of the following statements regarding the law of constant proportion are correct?
  1. It was given and stated by Lavoisier.
  2. In a chemical substance, the elements are always present in definite proportions by mass.
Select the correct answer using the codes given below:
Answer: Only 2
Notes: The law of constant proportion states that a chemical compound always contains its constituent elements in a fixed proportion by mass. This law was formulated by Joseph Proust, not by Lavoisier. Lavoisier contributed to defining elements and compounds, but the law itself is attributed to Proust.
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📌 Question Number: 145 in 91: Inorganic Chemistry in the above course in App.