Chemistry Key Concepts - Atomic structure

Transcription

1 Chemistry Key Concepts - Atomic structure What is an isotope? What is the atomic number? Why do atoms have no overall charge? How are atoms of different elements different? How does the size of an atom compares to the size of its nucleus? Why is the relative atomic mass of many elements not a whole number? What is the mass number? Where is most of the mass of an atom is found? the number of neutrons in an atom? the number of protons in an atom? the number of electrons in an atom? What is the mass number for these Iodine Chlorine Argon Iron How have our idea of what an atom looks like changed over time? What is the atomic number of these Chose an element, work out the number of protons, electrons and neutrons. (Show your working) Chlorine is 75% 35Cl and 25% 37Cl what is the relative atomic mass? (Show your workings) Hydrogen Nitrogen Helium the relative atomic mass of an element using the mass and abundance of its isotopes? Fill in this table Draw the structure of an atom as we know it today. Subatomic particles Relative charge Relative mass Protons Compare these two Iodine's. What are they called? Neutrons Electrons I I 53 53

2 Chemistry Key Concepts - The Periodic table What are the chemical symbols for these What did Mendeleev order elements by? What did Mendeleev do differently? Explain what the atomic number is. Where are metals in the periodic table? Where are non-metals in the periodic table? Nitrogen Hydrogen Oxygen Helium Iron Lead Chlorine Argon Gold What did Mendeleev do differently to other scientist? What evidence supported Mendeleev s idea? What is the electronic configuration of an element? What is the electron configuration of calcium? (Draw a diagram and write) How many electrons can you fit on the first 4 electron shells? What are the group and period for these 1 st 2 nd 3 rd 4 th Hydrogen Magnesium Argon Nitrogen How did Mendeleev predict the existence and properties of some elements yet to be discovered? (give an example of this) How are elements arranged in the modern periodic table? Label the periodic table What problems did Mendeleev have when ordering How did he rectify these? What is the link between an element s position in the periodic table and its electronic configuration?

3 Chemistry Key Concepts - Ionic and covalent bonding What is an ion? Explain the difference between compounds ending in ide and ate. Compare the similarities and differences between ionic and covalent bonds. What causes an ionic bond to form? Draw a diagram of an ionic compound as a lattice structure and explain arrangement of the ions and the forces between the atoms What are the positive ions called? What are the negative ions called? Explain the formation of ions for elements in groups 1,2,6 and 7 by completing the below table: Complete this dot and cross diagram for the covalent bonding of hydrogen and carbon. Group 1 Group 2 Group 6 Group 7 Outer electrons 1 Electrons lost or gained 2 lost Charge on ion 2 example F

4 Chemistry Key Concepts - Types of substance Explain why elements and compounds can be classified as: i. Ionic ionic compounds: covalent compounds: metallic compounds: ii. Simple molecular (covalent) iii. Giant covalent Explain the properties of fullerenes including C 60 and graphene. iv. Metallic Compare the similarities and differences between diamond and graphite Describe the structure of diamond Why are diamonds used in cutting tools? How are polymers e.g. poly(ethene) made? Describe the properties of metals Describe the structure of graphite Why is graphite used to make electrodes and lubricants?

5 Chemistry Key Concepts - Calculations involving masses Describe the limitations of: Dot and cross diagrams: Calculate the relative formula mass (M r ) of carbon dioxide (CO 2 ) Calculate the M r of calcium nitrate Ca(NO 3 ) 2 Describe an experiment to calculate the empirical formula of magnesium oxide. Ball and stick models 2D and 3D representations of compounds What is the empirical formula for CaCL 2 when 10.0g of calcium reacts with 17.8g of chlorine. Mass (g) Symbol for element Ca Cl Explain the laws of conservation of mass in a : Closed system Chlorine is 75% 35Cl and 25% 37Cl what is the relative atomic mass? (Show your workings) Relative atomic mass (A r ) Divide the mass of each mass by its relative atomic mass Divide the answers by the smallest number to find the simplest ratio Empirical formula A non-enclosed system Describe the properties of metals The empirical formula for glucose if CH 2 O and its relative formula mass (M r ) is 180. Determine the molecular formula for glucose. Find empirical formula mass Divide M r by empirical formula mass What is the molecular formula? Calculate the mass of chlorine needed to make 53.4g of aluminium chloride: Write the balanced equation Calculate the Mr s of the substances needed Calculate the ratio of masses (multiply Mr values by the balancing numbers shown in the equation Work out the mass for 1g of reactant or product Scale up or down (from 1g