### February 2017 archive

Redox reactions – basic notes and information document

Here is a link to the Khan academy video on balancing redox reactions in acidic solutions using half reactions. You may notice on the left of the page that there are other related videos there… we do not need to do this in basic solutions in this course.

Here is a simulation on Electrochemical cells where you can change the metals used and measure voltage

and another one here with some questions. It requires flash.

Today you need to determine the meaning of :

A) Metals, non-metals, metalloids, Halogens, noble gasses, alkali metals, alkali earth metals, lanthanoides, actinoides, s-block, p-block, d-block, f-block

For group A, determine where these are on a PT and mark them.

For group B, determine what the trend in these values are along a period and up or down a group, with a reason. Label the trend on the PT.

To think about, and answer (may require some looking up of information!) :

1. why is the trend in atomic radius not the same as the trend in ionic radius?
2. what are the differences/similarities between electron affinity and electronegativity?
3. why do different sources disagree on which elements exactly are metalloids (sometimes called semi-metals)?
4. what are alternate periodic tables? Why do scientists make them? Which one(s) do you like?

In class Feb 6, we looked for any misunderstandings or problems with material in 2.1 and 2.2. We were going to talk about mass spectrometres and isotopes and calculations but 8 people are away, so we’ve saved that for Wednesday Feb 15th.

Today we did this activity on patterns in Ionization energies, and why that is evidence for the organization of electrons. If you are not here, you should do it!

Our next lesson, on Feb 13th, we will talk about trends in the periodic table, discussed in 3.1 and 3.2 in the text.

To work on in class and after. Topic 2.1 and 2.2

Copy of handout here.

2.1

Simulation of Rutherford’s Gold experiment  https://phet.colorado.edu/en/simulation/rutherford-scattering

All about the nucleus, Bohr, etc in 10 minutes of fast talking from Crashcourse, get past the general chem first   https://www.youtube.com/watch?v=FSyAehMdpyI&list=PL8dPuuaLjXtPHzzYuWy6fYEaX9mQQ8oGr&index=1

Website (text) with More than you perhaps want to know about the operation of a mass spectrometre, but interesting http://www.chemguide.co.uk/analysis/masspec/howitworks.html

… and then how to use the information from a mass spectrometre to calculate ram  http://www.chemguide.co.uk/analysis/masspec/elements.html#top

Video (7 min) on mass spectrometry and how, why we use it https://www.youtube.com/watch?v=mBT73Pesiog

Topic 2.2

Models of the H atom sim How did scientists figure out the structure of atoms without looking at them? Try out different models by shooting light at the atom. Check how the prediction of the model matches the experimental results  https://phet.colorado.edu/en/simulation/hydrogen-atom

More history of atomic discoveries/models through the ages  https://www.youtube.com/watch?v=thnDxFdkzZs&list=PL8dPuuaLjXtPHzzYuWy6fYEaX9mQQ8oGr&index=37

Video on Light and atomic structure  (also has a link to the video transcript, if you’d like to read along)

Document from my drive on Electromagnetic spectra (in detail) https://drive.google.com/file/d/0B_gNjaR3kKGjSlpHNGhMUDBkNk0/view?usp=sharing

5 min clip on atomic emission spectra (from Brightstorm series) http://www.brightstorm.com/science/chemistry/the-atom/atomic-emission-spectra/

Do you wish you could see spectra at home? Clip of atomic spectra with home materials (optional)  https://www.youtube.com/watch?v=SdpY53AWCvY