The Law of Constant Proportions states that:
AReactions only happen at room temperature
BAll elements weigh the same
CAll compounds have the same mass
DIn a given compound, the elements are always present in the same fixed proportion by mass
Answer & Solution
Correct answer: D. In a given compound, the elements are always present in the same fixed proportion by mass
In a given chemical compound (like water — H₂O), the constituent elements (hydrogen, oxygen) are always combined in the same fixed proportion by mass — regardless of source. Water from a river or made in a lab is always 11.1% hydrogen and 88.9% oxygen by mass.
Related questions
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