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 chemical symbol for oxygen is O X N Y 2. The chemical symbol "Ca" represents which of the following elements? Carbon Sulfur Calcium Copper 3. The amount of a substance that can exist separately is called formulae molecule atom entity 4. Which one of the following is the chemical symbol for nitrogen? N K Nit Ne 5. The period in which an element is located gives us the number of electrons in its outer shell. the number of neutrons in that element. the number of electron shells that the electron has. the electronic configuration of that element. 6. The chemical symbol of silver is Au Ag Al Ad 7. The chemical symbol of potassium is D P K M 8. An atom of nitrogen has 7 protons and 7 neutrons in its nucleus. What is its electronic structure? 5,2 2,8,4 2,7 2,5 9. Which one of the following represents the compound called carbon dioxide? C CO2 H2O CO 10. Uniform mixtures are called solutions homogeneous heterogeneous terogeneous 11. Which one of the following substances is a compound? Hydrogen Oxygen Iron Sodium fluoride 12. Where two or more substances are mixed together but not chemically combined, this substance is called an atom a compound a mixture a molecule 13. Which one of the following statements is correct? Water is a compound and nitrogen is an element. Water and nitrogen are both elements. Water is an element and nitrogen is a compound. Water and nitrogen are both compounds. 14. Calcium is in group II (2) of the Periodic Table. How many electrons does it have in its outer shell? 2 11 4 20 15. The chemical symbol of gold is Au Ad Al Ag 16. If an element has an atomic number of 9 and a mass number of 19, then, which of the following statements is INCORRECT? There are 10 neutrons in its nucleus. There are 9 electrons orbitting around its nucleus. Its got 10 electrons and 9 neutrons. Its got 9 protons and 9 electrons. 17. Water is a compound made up of two different elements. These elements are Oxygen and iro Sodium and chlorine Hydrogen and nitrogen Hydrogen and oxygen 18. The following determine atomic no except neutron electron none of the above proton 19. Name the element that has an electronic structure of 2,4 Beryllium. Carbon. Oxygen. Calcium. 20. How many protons are there in an atom of sodium which has an atomic number of 11 and a mass number of 23? 23 34 12 11 1 out of 20 Time is Up! Time's up