Стр.140-141 Across the curriculum ГДЗ Комарова Ларионова 8 класс

6 Science Across the Curriculum

1. Match the elements with the correct symbols.

   1. H
   2. Fe
   3. N
   4. Ra
   5. Au
   6. C
   7. O
   8. Ne
   9. He
   10. Na
   11. Ca
   12. Pb
   1. Oxygen
   2. Sodium
   3. Carbon
   4. Hydrogen
   5. Iron
   6. Calcium
   7. Neon
   8. Gold
   9. Lead
   10. Nitrogen
   11. Helium
   12. Radium

2. Look at the periodic table and match the sections with the correct colour.

   1. Other metals
   2. Noble or inert gases
   3. Transition metals
   4. Semi-metals
   5. Non-metals

3. Read the text about elements and the periodic table. Complete the text with the words in the box.

   Positively, elements, atom, negatively, protons, nucleus

   There are only about 100 (1) ______ in the Universe. Elements contain one type of (2) ______. The atoms of an element are identical. For example, iron (Fe) atoms on Earth are the same as iron atoms found on Mars. Atoms have a (3) ______ in the middle which contain protons and neutrons. Protons are (4) ______ charged and neutrons are neutral. Electrons are (5) ______ charged and surround the nucleus. Elements in the periodic table are listed in order of their atomic number. The atomic number is the number of (6) ______ in the nucleus.

4. Read the text and answer the questions.

   Dmitri Mendeleev and the periodic table

   In the past, people believed that the world was made of four elements: earth, water, air and fire. In 1789, the French chemist Antoine-Laurent de Lavoisier published the first list of elements including oxygen, hydrogen and nitrogen. As scientists began to identify new elements, they tried to organize them in a logical sequence. Dmitri Mendeleev (1834–1907) was professor of chemistry at St Petersburg University in Russia. He developed an early version of the periodic table published in 1869. He arranged the elements into a table so that elements with similar characteristics are in the same vertical groups.

   1. What did people believe were the elements?
   2. Who published the first list of some elements?
   3. When was Mendeleev born?
   4. Where did he work?
   5. When did he publish his version of the periodic table?

Project

You are going to find out about two famous scientists.

Plan

Research

Find information about the two scientists and the area they worked in. Look in the library or on the Internet.

Prepare

Complete the table with your findings.

Present your material

Show your completed project to your classmates and teacher.