I offered a refresher of what you were already supposed to have learned in Chemistry A, or prior science classes. I am concerned that so many students seem not to understand the mole concept, scientific notation and significant figures. Further, most of you need to drill on basic math operations including long division and exponents. You had a homework problem: The diameter of the earth is 8,000 miles. The equation for the surface area of a sphere (e.g. -- our planet) is S = 4 Pi r^2 (where "r^2" means radius squared). We solved that. You were told that the length we call a "meter" was originally set at 1/10,000,000 the distance from the north pole to the equator. You were reminded that area of a circle is A = Pi r^2 and asked to find the surface area in square meters.
We discussed the number of particles in a mole: it is 6.02E23 (where "E23" is a short-hand way of writing "10 to the 23rd power.") We spoke of ways to memorize the number and how to use it. Basics of math were covered, like how to divide two numbers (the denominator goes into the numerator; not the other way around).
We started to discuss equilibrium, one of the topics we are to cover in Chem B. You were to read and summarize Ch. 14, section 3 in your text (HOLT, Chemistry). Instructions were given on how to "preread" a text. Homework for the weekend was to preread sections 1 and 2. I attempted to demonstrate equilibrium with salt solutions and acids, and it didn't work very well. I need purer chemicals to show you. We'll try again Monday.
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