give us something that is light blue, not yellow.

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Celsius-to-Fahrenheit: F = 1.8C + 32

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Presentation transcript:

give us something that is light blue, not yellow. QUESTION: Which of the following observations is a definite sign that a chemical change has occurred? Mixing a blue-colored liquid with a yellow-colored liquid, yields a green-colored mixture. Mixing a blue-colored liquid with a colorless liquid yields a yellow-colored liquid Neither Both Which of the following observations is a definite sign that a chemical change has occurred? …Mixing a blue-colored liquid with a yellow-colored liquid, yields a green-colored mixture. …Mixing a blue-colored liquid with a colorless liquid yields a yellow-colored liquid …Neither …or Both PAUSE An unusual color change is a definite sign that a chemical reaction has occurred. Choice A is not an unusual color change. Our eyes perceive a mixing of the colors blue and yellow as green. The observation given here does not necessarily mean that a chemical change has occurred. CROSS OUT CHOICE A Choice B is a definite sign that a chemical reaction has occurred. We would expect that a blue liquid mixed with a colorless liquid would give us something that is light blue, not yellow. Therefore, the correct answer is B. HIGHLIGHT B CLICK PAUSE END RECORDING

Video ID: 1-29-4 © 2008, Project VALUE (Video Assessment Library for Undergraduate Education), Department of Physical Sciences Nicholls State University Author: Glenn V. Lo Narrator: Johuan Gasery Funded by Louisiana Board of Regents Contract No. LA-DL-SELECT-13-07/08