Mole is a group count (just like dozen).

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Magnesium is Mg. Mn is manganese.

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Presentation transcript:

Mole is a group count (just like dozen). QUESTION: Which has more atoms? A. 1 mole of Mg-24, B. 1 mole of Mg-26 C. neither Mole is a group count (just like dozen). Analogous question: which has more eggs? A. 1 dozen small eggs B. 1 dozen large eggs Which has more atoms? A. 1 mole of Mg-24, B. 1 mole of Mg-26 C. neither PAUSE CLICK A mole is a way of counting, just like a dozen. CLICK So here’s an analogous question to help you understand the answer to this question. CLICK Which has more eggs 1 dozen small eggs, or CLICK 1 dozen large eggs Obviously, the answer is neither. They both have 12 eggs. One set just happens to weigh more. But the counts are the same. Therefore, the answer to this question is C. There are exactly the same number of atoms in one mole of magnesium-24 and one mole of magnesium-26. One just happens to have heavier isotopes. CLICK PAUSE END RECORDING

Video ID: 4-2-2 © 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