Students are learning to identify the important components of an electric circuit and describe how it works.
You will be able to collect the materials and connect them together to create a torch which includes a globe, switch, wires, batteries and reflector.
This week you will draw what you think is inside a torch (without dismantling it!) and then, after some discussion about the essential components, construct your own torch from simple materials. Imagine you are driving down the back paddock with Dad, and you get bogged in the ute. Dad has to walk back to get the tractor, to pull the ute out. It’s getting dark, so Dad tells you to wait in the car until he gets back. You look in the glovebox and find the following materials:
You unscrew the globe from the overhead light in the ute and start to make a torch. Your torch needs to be operated with one hand, and have a switch that turns the light on and off. A good torch will be able to direct a beam of light and have no loose wires or dangly bits. When you have finished please leave me a comment about what you found easy, what was more difficult and what you learnt from this activity. What do you think is the most important part of the torch?
Chromotography is a collective term for a set of laboratory techniques used to separate mixtures. It includes paper chromotography, thin-layer chromotography and gas chromotography. Paper chromotography is used for separating mixtures such as inks and dyes. In our practical experiment, we will use the natural food dyes used to colour “Smarties”, although the artificial colouring used for “M and M’s” work well too. This is also a great time of year to investigate the pigments in autumn leaves – as chlorophyll breaks down to produce xanthophyll, carotene and anthocyanin. Another experimental method for leaf chromotography here.
Why do some trees have leaves that change colour in the autumn? How is chromotography used by forensic scientists and in industry? Please do some research and post your answers in the comments section below.
photo © 2010 Bascom Oswald Hogue | more info (via: Wylio)
The drawing above is from Wylio, a great place to search for free-to-use images for your blogs and wikis. It shows a diagram of the model of an atom, with a central nucleus and the path of three electrons around the outside. Elements are pure substances consisting of just one type of atom. Compounds are made up of molecules that consist of more than one type of atom. All the known elements are arranged in the periodic table in order of their atomic number.
During today’s lesson we will be looking at a range of different elements and describing them. You will use the Google doc, “Investigating Elements” to record your results. Click on the link and download the document onto your computer. There are 14 different elements to observe and complete each column – name, symbol, atomic number, description and what you might find that element in. We will also have some time this week to use the iPads to investigate “The Elements” app, which has amazing interactive images of each of the pure elements and extensive information about each element. This app can be purchased through the iTunes store for $13.99.