Northern NSW da Vinci Decathlon

Transcription

1 Northern NSW da Vinci Decathlon An academic gala day for years 9 and 10 Science Session 1 Where the spirit does not work with the hand, there is no art Leonardo da Vinci. Team Number 1

2 Light and Colour through Paint and Paintings One of the earliest technologies that humans invented was the making of paint. By using different coloured earth, or grinding soft rocks to a powder, early people could make pictures of different colours. The first use of minerals was for cave painting. The Egyptians used minerals in their cosmetics and for tomb painting. Australian Aboriginal painters used earth colours - reds, browns, and yellows, black and white - from ochres and other minerals Renaissance Art The French term Renaissance emerged in the 19th century and was used to describe an entire period of rebirth, occurring between the 14th and 17th centuries. Artists of this time looked back to those before them while incorporating a greater sense of light and colour through new medium. Leonardo da Vinci. The Last Supper Santa Maria della Grazie, Milan, late 15 th Below is a commentary on the above painting. Leonardo clearly understands linear perspective as well as the importance of light as the unified light source in the painting is related to the real light source. Christ sits in the middle with his arms spread out in a pyramid shape, symbolizing stability, equality, and permanance. The apostles around him are grouped in threes which gives a balance to the whole and maintains a sense of visual unity. Gestures and colours link one group to the next and allow the narrative to flow. Facial expressions of each figure are very individual allowing the viewer to follow the story. 2

3 Task The Science challenge is inspired by the importance of Renaissance Art and will show the interrelatedness of Chemistry and Art. During the Renaissance, it was common for an artist to do a painting and then have students replicate the painting. The replica was signed by the real artist despite it not being authentic. Numerous examples of the one piece circulated; a real one and several replicas. In this task you will act as an Art Conservation Chemist. You will consider the materials and methods used by artists to make art work (not necessarily paintings) and answer questions based on a simulated forensic investigation that considers techniques that could be used to determine if a substance is authentic or a replica. Setting the Scene A museum is about to hold an exhibition to demonstrate how authentic art has been replicated through the ages. As the artefacts were transported to the museum, they got mixed up and the curator of the exhibition now has to determine the authentic pieces from the replicas. In each scenario, you will be presented with an example of how an authentic piece of art can be replicated. This provides the starting point from which you will be asked questions that examine a broad range of science concepts. Answers go on the separate answer sheet. Answers are not to go beyond the space provided. 3

4 Scenario 1: Aluminium v Stainless Steel - which is older? Aluminium is a commonly used metal today, but prior to 1886 (when a cheaper way to purify aluminium was discovered) it was only used for special reasons such as making fine jewellery. In the early 1800 s, stainless steel was discovered. 19 th Century aluminium used to create fine jewellery was replicated with the less expensive stainless steel. The curator has to distinguish a piece of authentic aluminium jewellery from a stainless steel replica. An experiment can be set up to distinguish between the two metals. The materials are illustrated in the photos below. Questions 1. Identify two current uses of aluminium. 2. Describe what stainless steel is. 3. Using the materials shown in the photos, and regular school laboratory glassware, outline a valid experimental procedure that will accurately distinguish between aluminium and stainless steel. 4. Using a ruled table, predict the expected results and observations you would expect in this experiment. 4

5 Scenario 2: Prussian Blue or Ultramarine Blue? Two paintings were part of the artefacts. They both have blue pigment. The curator knows that the older authentic painting will have an older pigment called Ultramarine Blue (used from the 12 th Century) and the replica will have a pigment called Prussian Blue (used since the 18 th Century). Luckily for the curator there is some excess canvas at the back of the paintings so some of this can be sampled. Prussian Blue can be made, as shown in the photos below. Ultramarine Blue is sourced from natural sources (even though it can now be made artificially). The photos show how to make Prussian Blue and a chemical test that can be used to distinguish Prussian Blue from Ultramarine Blue. Photo 1 How to make Prussian Blue pigment 5

6 Photo 2 - Turning Prussian Blue pigment into a paint. Photo 3 A chemical test to distinguish Prussian Blue from Ultramarine Blue 6

7 Questions 1. There are a number of solutions shown in the photos. What is a solution? 2. What is the name and charge of the ion with the symbol K in the yellow solution? 3. What is an ion? 4. How many atoms/ions in the chemical that comprises the yellow solution? 5. What is the chemical formula for sodium hydroxide? 6. What is the name of the compound with the formula CaCO 3? 7. Consider the chemical reaction that results in the formation of Prussian Blue FeCl 3 + K 4 Fe(CN) 6 à KFe(II)Fe(III)(CN) 6 + 3KCl (a) In Prussian Blue, iron exists in two forms. In a sentence describe the two ways iron exists. (b) The interaction between the two forms of iron results in the blue colour. Describe why objects are blue by making reference to the visible spectrum. 8. Ultramarine Blue was originally discovered by grinding lapis lazuli? What is lapis lazuli? 9. Summarise the test to distinguish Prussian Blue from Ultramarine Blue. In your answer refer to the terms destructive and non-destructive testing. Scenario 3: Sampling ink using chromatography The curator has noticed that a particular piece of artwork used different inks. Chromatography can be used to authenticate inks on old documents. The authentic sample used water based ink. These types of ink have been used for a long time as compared to non-water based inks. The replica used non-water based ink. A sample of each ink was extracted and tested using chromatography. The results are presented in the photos that show the progression of the experiment. 7

8 Photo 1: Start of the experiment Photo 2: Mid-way point of the experiment 8

9 Photo 3: The end product Questions 1. Why do objects appear black? 2. Propose a reason why water based inks have been around longer than non-water based inks. 3. Use the photos of the experiment to summarise the principles of chromatography. Scenario 4 Glass or plastic? The final artefact that needs to be classified is a glass object from the Renaissance that was used in one of the first attempts to make a microscope. The replica has been recently replicated using polymer technology. UV radiation will pass through glass but not some (plastic) polymers. Analyse the results in the accompanying photos. 9

10 Photo 1: UV radiation (source bottom left) directed into glass Photo 2: UV radiation (source bottom left) directed into a plastic polymer 10

11 Questions 1. Present the results as a scientific diagram 2. Identify two components of glass. 3. Glass is an amphorous substance as a result of the way the components are arranged following the melting and resolidification process to make it. Draw a diagram that shows an understanding of the term amphorous. 4. Glass is made naturally in volcanoes. What is this geological glass called? 5. What is a polymer? Answer this through a simple, annotated diagram. Bibliography American Chemical Society n.d., 'State of the Art Chemistry: A Hands-On Program', American Chemical Society, Cleveland, USA, Chemistry%26Art_script.pdf [accessed 17 March 2013] 11

12 Answer Sheet Science Scenario 1 Aluminium v Stainless Steel which is older? Q1 Identify two current uses of aluminium. Q2 Describe what stainless steel is. Q3 Using the materials shown in the photos and regular school laboratory glassware, outline a valid experimental procedure that will accurately distinguish between aluminium and stainless steel. /4 Q4 Using a ruled table, predict the expected results and observations you would expect in this experiment. /5 12 /13

13 Scenario 2 Prussian Blue or Ultramarine? Q1 There are a number of solutions shown in the photos. What is a solution? Q2 What is the name and charge of the ion with the symbol K in the yellow solution? /1 Q3 What is an ion? /1 Q4 How many atoms/ions in the chemical that comprises the yellow solution? /1 Q5 What is the chemical formula for sodium hydroxide? /1 Q6 What is the name of the compound with the formula CaCO 3? /1 Q7 Consider the chemical reaction that results in the formation of Prussian Blue FeCl 3 + K 4 Fe(CN) 6 à KFe(II)Fe(III)(CN) 6 + 3KCl (a) In Prussian Blue, iron exists in two forms. In a sentence describe the two ways iron exists. (b) The interaction between the two forms of iron results in the blue colour. Describe why objects are blue by making reference to the visible spectrum. /3 13

14 Q8 Ultramarine Blue was originally discovered by grinding lapis lazuli? What is lapis lazuli? /1 Q9 Summarise the test to distinguish Prussian Blue from Ultramarine Blue. In your answer refer to the terms destructive and non-destructive testing. /15 14

15 Scenario 3 Sampling ink using chromatography Q1 Why do objects appear black? Q2 Propose a reason why water based inks have been around longer than non-water based inks. Q3 Use the photos of the experiment to summarise the principles of chromatography. /3 /7 15

16 Scenario 4 Glass or plastic? Q1 Present the results as a scientific diagram /3 Q2 Identify two components of glass. Component 1. Component 2. Q3 Glass is an amphorous substance as a result of the way the components are arranged following the melting and resolidification process to make it. Draw a diagram that shows an understanding of the term amphorous. Q4 Glass is made naturally in volcanoes. What is this geological glass called? /1 Q5 What is a polymer? Answer this through a simple, annotated diagram. 16 /10