16/12/2019 Atoms, Compounds and Mixtures (STUDY BY TOPICS JUNIOR CLASS) 16/12/2019 0Comments by Gate Academy Welcome to your Atoms, Compounds and Mixtures (STUDY BY TOPICS JUNIOR CLASS) NAME EMAIL PHONE NUMBER 1. The following are examples of heterogeneous mixtures except sugar solution air salt solution petroleum 2. An atom of nitrogen has 7 protons and 7 neutrons in its nucleus. What is its electronic structure? 2,7 2,8,4 2,5 5,2 3. When a substance is analysed using an electron microscope, it is found to contain only one type of atom.This substance is a mixture neither of the other three an element a compound 4. The chemical symbol for oxygen is X Y O N 5. How many different types of atom may be present in a compound? Two or more different types Three or more different atom types Only one type of atom Exactly four different atom types 6. The period in which an element is located gives us the number of electrons in its outer shell. the number of electron shells that the electron has. the electronic configuration of that element. the number of neutrons in that element. 7. Approximately how many elements are there on earth? 1000 100 10 20 8. How many neutrons does the element of atomic number 1 and mass number 1 have? 1 0 None of other mentioned values 2 9. How many protons are there in an atom of sodium which has an atomic number of 11 and a mass number of 23? 23 11 34 12 10. Which particles are to be found in the nucleus of an atom? Electrons and neutrons. Neutrons only. Neutrons and protons. Protons, neutrons and electrons. ? ? ? 11. The following are products of fractional distillation of crude oil except kerosene octane bitumen naphta 12. The chemical symbol of silver is Ag Au Ad Al 13. The properties of a compound will be the same as the properties of the elements that make up the compound False True 14. Where are the electrons located in an atom? Attached to the protons. Orbiting around the nucleus. Inside the nucleus. Attached to the neutrons. 15. Who founded the atomic theory Blaise Pascal John Dalton Roger Williams Micheal Faraday 16. Which one of the following statements is correct? Water and nitrogen are both compounds. Water is an element and nitrogen is a compound. Water and nitrogen are both elements. Water is a compound and nitrogen is an element. 17. Calcium is in group II (2) of the Periodic Table. How many electrons does it have in its outer shell? 4 20 2 11 18. Study the four diagrams representing different substances. Which two of these diagrams represents elements? A and B B and C A and D C and D 19. Which one of the following substances is a compound? Iron Hydrogen Sodium fluoride Oxygen 20. Which one of the following represents the compound called carbon dioxide? CO C CO2 H2O 1 out of 20 Time is Up! Time's up
