What do you know about science?
Can science be cool? What do you know about metals? Some metals such as the one in the following article have very special and unusual qualities. Do you know what temperatures some metals melt at or their effects on other metals is? Do you know any famous scientists who discovered metals? |
Look at the questions below and see if you already know the answers.
To check your answers, read the text again. Write you answers in full sentences before finally looking at the next section to see if you were right. 1. What's so unusual about the melting point of gallium? 2. What other interesting characteristic has the metal got? 3. According to the text what happened in 1871 and 1875? 4. What did Mendeleev's predictions include? 5. Where was gallium found? 6. Pure galium cannot be found naturally but can be formed by separating other metals. Which two words can be used to replace the two underlined words in sentence 6? 7. We learn that gallium is silver in colour, has glass-like qualities and combines (alloys) with other metals, what can it be used to stabilise? 8. What is gallium used for today? |
Here are the answers:
1. What's so unusual about the melting point of gallium? The melting is very low, only 29.76 degree Celsius. 2. What other interesting characteristic has the metal got? It can attack other metals weakening them (making them weak). 3. According to the text what happened in 1871 and 1875? In 1871 Dmitri Mendeleev predicted the metal (he believed it existed), and in 1875 Paul Emile Lecoq de Boisbaudran discovered it. 4. What did Mendeleev's predictions include? He predcted many of its properties, including its density, melting point, oxide character and bonding in chloride. 5. Where was gallium found? In a sample of sphalerite. 6. Pure galium cannot be found naturally but can be formed by separating other metals. Which two words can be used to replace the two underlined words in sentence 6? Elemental can mean pure in this sentence and taken can be replaced with smelting. 7. We learn that gallium is silver in colour, has glass-like qualities and combines (alloys) with other metals, what can it be used to stabilise? It can be used to stabilise plutonium in nuclear bombs. 8. What is gallium used for today? Today gallium is used for microelectronics and cars. It is also used for microwave circuitry and infrared devices. |