QUESTION: A 25.0 gram sample of a compound is found to be 24% chlorine by mass. What is the percentage of chlorine in a 50.0 g sample of the compound?

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Presentation transcript:

QUESTION: A 25.0 gram sample of a compound is found to be 24% chlorine by mass. What is the percentage of chlorine in a 50.0 g sample of the compound? A. 24%, B. 48%, C. 12% D. It depends where the sample came from The Law of Definite Composition says that the percentage of each element in any sample of the compound (as long as it’s pure) is constant. This law is also known as the Law of Definite Proportions, or the Law of Constant Composition. SCRIPT: A 25.0 gram sample of a compound is found to be 24% chlorine by mass. What is the percentage of chlorine in a 50.0 g sample of the compound? A. 24%, B. 48%, C. 12% D. It depends where the sample came from PAUSE CLICK. The Law of Definite Composition says that the percentage of each element in any sample of the compound (as long as it’s pure) is constant. Therefore, the correct answer is A. If one sample of the compound is 24% chlorine. Any other sample of the compound is also 24% chlorine. CLICK This law is also known as the Law of Definite Proportions, or the Law of Constant Composition. PAUSE END RECORDING.

Video ID: 1-9-1 © 2008, Project VALUE (Video Assessment Library for Undergraduate Education), Department of Physical Sciences Nicholls State University Author: Glenn V. Lo Narrator: Funded by Louisiana Board of Regents Contract No. LA-DL-SELECT-13-07/08