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Help with beginner chem stuff

  1. Sep 14, 2004 #1
    i have this chem teacher who does NOT teach from the book at all! he just expects us to read the book and understand it completely. so yeah i have a few questions that i cant do!

    how long would it take a plane, traveling at an average speed of 634km/h, to cover a distance of 3912 km?

    Determine the mass in grams of a hamburger that weighs 8.0 oz.

  2. jcsd
  3. Sep 14, 2004 #2
    Your first question is not a chemistry question. Your second question has little to do with chemistry.

    You should know that Time = Distance/Speed.

    You should also know that 1 oz. = 28.35 g.
  4. Sep 15, 2004 #3


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    The first chapter is usually on non-chemistry basics, such as unit conversions, significant digits, etc.

    Yes, speed = distance/time ..... or you can rearrange the equation to find either of the other two missing variables.

    You should have a chart (either in one of the appendices or on a handout) that shows conversions from metric to english or english to metric. You use the dimensional analysis to eventually arrive at the proper units.

    For example: to go from meters/second to miles/hour you have to multiply by (1 mile/1609 meters) and by (3600 seconds/1 hour).

    The conversion can be flipped either way (1609 meters/1 mile) since the numerator and denominator are equivalent (1609 meters = 1 mile). You choose which way to flip it depending upon which unit you want to cancel out.
  5. Sep 15, 2004 #4


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    Out of curiosity starsun, which grade is this for/are you in ?
  6. Sep 15, 2004 #5


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    Dear starsun, you have not started the real thing yet... I hope you'll like chemistry lessons after you understand these unit conversions, You will need them in the future, so don't be confused.

    Regards, chem_tr
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