עמוד:10 Elements and the variety of materials in the world Currently there are about 70 , 000 , 000 materials in the world , and thanks to discoveries and developments made by various scientists , the number of known materials is increasing every minute . How is it possible that such a vast variety of materials can be made from just 90 naturally occurring elements ? This is what we will investigate in the following activity . Activity Experimentation Combining letters The English alphabet has 26 letters . 1 . You have three letters : D , M , A 2 . In your notebooks , write different combinations of these three letters . You can use all of the letters or just two of them , and you can use the same letter once or twice . 3 . How many combinations have you made ? 4 . Which of these combinations make up meaningful English words ? Circle those words . How many words have you made ? 5 . In this activity we have used a model to demonstrate how the variety of materials in the world can be obtained from different combinations of the elements . A . In the following table compare the model with reality . B . How is the model different from reality , and how is it similar ? C . How has the use of the model helped you understand the variety of materials in the world ? D . Suggest another model that can demonstrate this . Smartphones are made of hundreds of different materials
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