Match the number with the definition!
1. of atoms 2. chemical element (such as iron, etc.) 3. an age in history 4. power 5. two or more forms of a chemical element 6. dull blue-gray metal 7. sheds radiant energy 8. product of uranium 9. smallest particle 10. form an opinion about 11. simple substance 12. radioactive element Uranium In 1789 a new element was found to exist and was named after the planet Uranus. This element, uranium, slowly revealed its radioactive secrets. It came to be most important because it yielded radium, a substance which could heal such diseases as cancer. Uranium's full value was not actually known until the arrival of the atomic age. This era was brought about when scientists discovered that atoms could be split, thus creating atomic energy. Uranium has three natural isotopes U-234, U-235, and U-238, the last two being used more often. The isotope U-235 is used in making the atomic bomb The more abundant U-238 is a source of plutonium, which is used in creating atomic energy. With the discovery of uranium, scientists have also been able to tell the age of the earth. For pure uranium, a shiny, silver-colored metal, eventually turns to lead. By finding out how long it takes for this change to occur, scientists can estimate the earth's age. Questions Remember, spelling counts! 13. The isotope U-238 is a source of _____ . 14. _____ has helped scientists determine the age of the earth. 15. Atomic _____ was discovered when scientists found that the atoms could be split. 16. Uranium was discovered in the year of _____ . 17. Uranium has three natural _____ . 18. Uranium turns to _____, and this is how the scientists determine the age of the earth. Your score is out of 18
Uranium In 1789 a new element was found to exist and was named after the planet Uranus. This element, uranium, slowly revealed its radioactive secrets. It came to be most important because it yielded radium, a substance which could heal such diseases as cancer. Uranium's full value was not actually known until the arrival of the atomic age. This era was brought about when scientists discovered that atoms could be split, thus creating atomic energy. Uranium has three natural isotopes U-234, U-235, and U-238, the last two being used more often. The isotope U-235 is used in making the atomic bomb The more abundant U-238 is a source of plutonium, which is used in creating atomic energy. With the discovery of uranium, scientists have also been able to tell the age of the earth. For pure uranium, a shiny, silver-colored metal, eventually turns to lead. By finding out how long it takes for this change to occur, scientists can estimate the earth's age. Questions Remember, spelling counts! 13. The isotope U-238 is a source of _____ . 14. _____ has helped scientists determine the age of the earth. 15. Atomic _____ was discovered when scientists found that the atoms could be split. 16. Uranium was discovered in the year of _____ . 17. Uranium has three natural _____ . 18. Uranium turns to _____, and this is how the scientists determine the age of the earth. Your score is out of 18