Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

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


    User Avatar
    Science Advisor
    Homework Helper

    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


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

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


    User Avatar
    Science Advisor
    Gold Member

    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
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: Help with beginner chem stuff
  1. Help I Suck At Chem (Replies: 1)

  2. Chem help please? (Replies: 3)