Class of 09-Feb-2016.
We did a mini-lab today on Classifying Elements! Please take a look at the marking checklist (in another post) to see the instructions and how I will be marking it.
We will be having a quiz tomorrow morning on Chapter 6. You will need to know how to do the following things:
Given an element, determine atomic number, # protons, # electrons, # electrons, mass number, atomic mass, chemical symbol, chemical formula, and chemical family. You will also need to know how to classify a material as a pure substance, element, compound, or mixture. You will have to know how to draw a Bohr diagram.
You WILL be given a periodic table.
As an interesting fact, helium is one of the rarest elements on the planet. Helium accounts for 0.00052% of the atmosphere, which is almost nothing! Most of it is instead extracted from minerals and natural gas deposits in the ground, both of which are finite resources. People keep using helium for balloons, making it even more rare and expensive to buy for scientific research. There is now talk about banning helium balloons because of this! Helium is selected because it is very unreactive. Which other elements could be used to fill balloons based on this quality?