Monday, November 30, 2020

Recovering Gold from e-Waste

 We use electronic devices every day; computers, drones, home security systems, mobile phones, smart speakers, smart watches, etc. If the device stops working, or we want to upgrade to a newer version, we throw away the old device resulting in electronic waste or e-waste. Each of these devices contains a printed circuit board (PCB) and the metal content of each PCB can be as high as 40% by mass. 

Recycling 1 tonne of mobile phones alone could produce more than 130 kg metal, including about 340 g of gold. The value of just the gold in that tonne of rubbish is over $25,000(AUD). Recovering metal from waste electronics and electrical equipment is becoming big business, but what impact does this have on us and our environment?

 Read this edition of AUS-e-NEWS to find out more ...

You can subscribe to AUS-e-NEWS, AUS-e-TUTE's free quarterly newsletter for chemistry students and teachers, at 

https://www.ausetute.com.au/ausenews.html

Saturday, November 7, 2020

Arrhenius Acids and Bases

What is an acid?

What is a base?

These are both good questions and there is no simple answer.

It all depends on how you decide to define the terms "acid" and "base".

More than 100 years ago, a clever chemist by the name of Arrhenius proposed the first really useful definitions of acids and bases and AUS-e-TUTE has just added a new tutorial, game, test and exam (with worked solutions!), and even some flash cards o help you understand and apply the Arrhenius definition of an acid and of a base.

Not an AUS-e-TUTE Member? You can go to a free-to-view tutorial at 

https://www.ausetute.com.au/arrheniusab.html