In-Class Problem Set #01

If you want to check your answers to the first problem set we looked at in class, here's the link:


I hope studying is going well, let me know if you have any additional questions. And don't forget, if you need a little study break tomorrow afternoon, the Dragon Soccer team has a home game at 3pm. After today's rain, tomorrow looks like it will be a lovely day to watch some soccer.


  1. Hi Dr. Bodwin! I have a question regarding number eleven on the 2011 exam... The solution for the question has six sig figs but the sig figs for strontium is only four. Is it suppose to be four or six?

  2. Hmm, sorry I didn't see this comment sooner, I usually see emails quicker... The question you asked about does have a sig fig rounding error, but it's neither 4 nor 6, the answer should be rounded to 5 sig figs. When adding and subtracting numbers, don't count the number of sig figs, count the number of decimal places. Since the strontium atomic mass is rounded to the hundredths decimal place (and the rest are to the thousandths), the result should be rounded to the least precise input and rounded to the hundredths decimal place.