Science video: how to make gold alloy?

 Grade Seven Science: Solid-Solid Mixtures (alloys)

Copy and paste the following in Google Doc

 

Gold alloy (first video, composition of 24K, 22K, 18K gold, and how it is calculated)

https://www.youtube.com/watch?v=8rQ0SkItHH0

 

1.    Purity of gold is calculated in the unit ___________ or __________ and not carrot

 

2.    Maximum purity of gold is _______K or 100% pure gold

 

3.    Pure gold is very ________ and can _________ easily

 

4.    We need to add other metals to make it ___________

 

5.    18K gold is _____% pure. Show your calculations:

 

6.    12K gold is _____% pure. Show your calculations:

 

7.    20K gold is _____% pure. Show your calculations:

 

8.    Alloying is mixing gold with other ____________

 

9.    Chemical symbol for gold is __________; 

 

10.Chemical symbol for silver is __________

 

11.Chemical symbol for copper is __________

 

12.When we combine ________ and _______, we get white gold

 

13.When we combine ________ and _______, we get reddish rose gold

 

 

This video shows you how gold alloy is made.  Cool

https://www.youtube.com/watch?v=vd93NeJcopY

 

14.  To begin, the woman uses 1oz of _________ pure fine gold, 1 Pennyweight ______ grains of silver and __________ grains of copper

 

15.  0.9999 gold = 99.99% pure gold

 

16.  She uses the hard compressed __________ block to press the gold nuggets

 

17.  Always __________ while heating

 

18.  Tips 2: try to get the gold nuggets as _________ and ________ as possible

 

19.  She tries to keep the ____________ steady. When the melted gold forms a _______ it is ready for mixing and alloying

 

20.  How to check for purity after melting? Looking for __________ finish and __________ on the gold ball

 

21.  The alloy is this video is a mixture of gold, ________ and _________. 

 

22.  This forms a ____K gold alloy

 

23.  First, she adds _________ to the melted gold. Follows by adding ___________

 

24.  The colour of the 22K gold alloy is _________ than pure gold

 

25.  After turning off the torch, let the alloy cools to a _________, then put it in ________ and we hear a hissing ____________

 

26.  We must let the alloy sits in the water bowl for a while for it to cool off completely