Tag Archives: science

Tools for teachers to utilize for “Hour of Code”week.

HERE is an article from SmartBrief that lists 5 different platforms that offer introductory activities for students. Such activities include: Minecraft, Angry Birds, Pong, and JavaScript to name a few.

Happy Mole Day!

October 23 from 6:02 in the morning to 6:02 in the evening is Mole Day!  This is a time for all scientists and aspiring scientists, to celebrate the conversion factor to end all conversion factors:  The Mole

6.022 x 10^23

A Mole is 602200000000000000000000 of anything, Similar, but much larger, to a dozen which is 12 of anything.  This useful number helps us to convert from thinking at the atomic scale to the macroscopic scale where you and I can see and experiment with it.

How useful is a Mole?

A mole is the amount of pure substance containing the same number of chemical units as there are atoms in exactly 12 grams of carbon-12 (i.e., 6.023 X 1023). This involves the acceptance of two dictates — the scale of atomic masses and the magnitude of the gram. Both have been established by international agreement. Formerly, the connotation of “mole” was “gram molecular weight.” Current usage tends to apply the term “mole” to an amount containing Avogadro’s number of whatever units are being considered. Thus, it is possible to have a mole of atoms, ions, radicals, electrons, or quanta. This usage makes unnecessary such terms as “gram-atom,” “gram-formula weight,” etc.

All stoichiometry essentially is based on the evaluation of the number of moles of substance. The most common involves the measurement of mass. Thus 25.000 grams of water will contain 25.000/18.015 moles of water, 25.000 grams of sodium will contain 25.000/22.990 moles of sodium.

The convenient measurements on gases are pressure, volume, and temperature. Use of the ideal gas law constant R allows direct calculation of the number of moles: n=P V/R T.  T is the absolute temperature, R must be chosen in units appropriate for P, V, and T. The acceptance of Avogadro’s law is inherent in this calculation; so too are approximations of the ideal gas.

How to Celebrate Mole Day.

Mole Day Celebrations may include songs, games or special baked goods as shown below:

Mole cupcakes.

It’s a time to have fun and relax with a bit of humor too.

Mole day Jokes:

Why did Avagadro want to be a dentist?

A. So he could work on Molars

What is Avagadro’s favourite dip?

A. Guacamole

What does Avagadro like to put on his pancakes?

A. Molasses