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עמוד:31
Summary Questions 1 . Indicate which of the following statements is correct . A . Only living creatures are made of atoms . B . Both living creatures and objects are made of atoms . C . Only objects are made of atoms . D . Only elements are made of atoms . 2 . Which of the following answers contains only elements ? A . Water , air , table salt , olive oil B . Carbon dioxide , water , sulfur , oxygen C . Oxygen , hydrogen , carbon , sulfur D . Oxygen , water , carbon , sulfur 3 . Which of the following figures describes a substance that is not an element ? Explain . 4 . Complete the following statement . An atom consists of a tiny , compact _________ , in which positively charged _________ and neutral _________ are present . The _________ are negatively charged particles forming a "cloud" around the nucleus . 5 . A new planet was recently discovered and was found to contain a very high concentration of an element whose atomic number is 6 . Which element is this ? How many protons and how many electrons does it contain ? 6 . How many protons and electrons are there in a positive potassium ion ( K )? ( Use the periodic table ) A . 19 protons , 19 electrons B . 20 protons , 19 electrons C . 19 protons , 18 electrons D . 19 protons , 20 electrons
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