Ex.2 Answer the following questions. 1. How are elements arranged in the Periodic table?
2. What can periodic table predict?
3. Does californium exist naturally?
4. What does the Periodic Law state?
5. Who developed the Periodic Table?
Ex.3 Complete the sentences. Use in, at, on. 1. Liquid is ……the flask.
2. You can fine the properties of chemical elements … the periodic table.
3. She will come to the laboratory … 5.30.
4. The book about the properties of metals and nonmetals is … the table.
5. We have our chemistry lesson at school … Tuesday.
6. I will calculate the molecular mass of this chemical compound … two minutes.
7. Look … the blackboard ! I am writing a chemical equation.
Ex. 4 Correct the mistakes in the following sentences. 1. Put the bottle with the explosive liquid at the table.
2. I don’t know the name of this chemical compound which is written in the blackboard.
3. There is nothing on this room.
4. You should send me your paper on my-email.
5. You can find the atomic number of this chemical element at the Periodic table.
6. This solution should be placed at the electrolytic cell.
7. This chemical reaction occurs in high temperature.
Ex. 5 Put the questions to the bold-typed words. 1. The Periodic table was created by Dmitri Mendeleev in 1869. 2. The Periodic table can help predict the properties. 3. Isotopes have only strengthened the idea. 4. Yesterday we studied the Periodic Law. 5. The Periodic table provides useful information.
6. His confidence was clearly expressed in the predictions.
7. The Periodic Law states many interesting facts.