Chemistry Reading Project -- Silver 3D Group 6 : LIN Lok Kwan(28) NG Wing Yan(29) NG Yim Hung(30) WONG Hoi Ki (33)

Content Introduction of ‘Silver’ Reason of choosing this book About silver History of silver The most impressive extract How silver used in photography Daily application of silver Experiment(with conclusion) How does “Silver” affect our thoughts about chemistry Our comments Duty list Resources

Introduction of ‘Silver’ Author : Salvatore Tocci Summary :  Information of silver  History of silver (reasons of why silver is precious)  Usage of silver  Some experiments about silver  Some fun facts about silver

Why do we choose this book? Silver is around our daily life But we may not know how to use it So we want to know more about it

About silver… Symbol Ag Atomic Number 47 Number of Protons/Electrons 47 Number of Neutrons 61 Classification Transition Metal Name Origin From the Old English word seolfor (silver) Symbol Origin From the Latin word argentum (silver)

One of the first five metals discovered and used by humans. The others were gold, copper, lead and iron. A shiny, bright, grayish, malleable and ductile metal (only gold is more ductile than it) Not easily being corrode or rust ( except sulfur, nitric acid, hydroiodic acid, chlorine,etc) Tarnish easily (when combined with sulfur) Comes from ores which found in Earth’s crust The best conductor of electricity

History of silver… Some 6000 years ago, the ancient Egyptians wore jewellery made of silver. In the late 1850s,miners discovered a huge supply of argentite in Nevada. So much silver was recovered that the huge supply caused its price to fall.

In ancient times, one of the main uses of silver was in making coins. The first silver coins were made about 2600 years ago by people living in an area that is now part of Turkey. Today,only 5 % of the silver that is mined is used to make coins.

The most impressive extract… Silver can be used in many aspects For example, jewellery, medicine, photography, x-ray, eating utensils, serving trays, decorative objects one-way mirror and coins, etc. We most concerned about how silver used in photography.

How silver used in photography? Both photographic film and paper contain a silver compound. When it is struck by light,the silver in this compound turns into pure silver and becomes darker. The silvers helps to form the images that appear on black-and-white film or paper. Color prints are also made with the use of silver,along with dyes that are added.

Applications of silver in daily life… Spoon Jewellery Food Containers Iphone case Door handle Keyboard skins

Tabmint One-way mirror Electricle switches

Experiment Time! Cleaning the silver coins Materials : Let ’ s Do It !!! Aluminum foil Hot water (100 °C) A tarnish coin Baking soda

Step 1 Step 2 Step 3 After a few minutes… Amazing !

Conclusion of the experiment… The tarnish-removal method used in this experiment uses a chemical reaction to convert the silver sulfide back into silver In this experiment, the silver sulfide reacts with aluminum Formula of the reaction Link of the video about the experiment :

Our comments This book introduced silver to us in detail (e.g. history and daily usage etc. ) Silver seems to be very close to us but we may not pay much attention to it However, after reading this book, we have learned about silver.

Duty list LIN Lok Kwan : Finding book NG Wing Yan : Finding photo NG Yim Hung : Finding information WONG Hoi Ki : Finding experiment’s video

Resources =sbUjVY72IIO3mAXe9ICACA&ved=0CCkQ1QIoBA#imgdii=_&imgrc=A_a0wGJUfHyoHM%253A%3BRzlpWNQvt YBOzM%3Bhttps%253A%252F%252Fnativeamericanjewelrytips.files.wordpress.com%252F2012%252F08%252F silver- bar.jpg%253Fw%253D584%3Bhttps%253A%252F%252Fnativeamericanjewelrytips.wordpress.com%252F2012% 252F08%252F28%252Fwhat-is-my-scrap-sterling-silver-jewelry-worth%252F%3B300%3B300 ved=0CAgQ_AUoAQ&biw=1280&bih=899 ved=0CAgQ_AUoAQ&biw=1280&bih=899