BTEC Applied Science Unit 1 Chemistry

How many electrons can an s subshell hold? - Answer - 2 How many electrons can a p subshell hold? - Answer - 6 How many electrons can a d subshell hold? - Answer - 10 Which subshells are available in the first energy level? - Answer - s Which subshells are available in the second energy level? - Answer - s and p Which subshells are available in the third energy level? - Answer - s, p and d What is Hund's rule? - Answer - Orbitals must all be singly filled before they can be doubly occupied Which elements do not fill the 4s subshell before the 3d subshell? - Answer - Copper and chromium Define the term ionic bond - Answer - The electrostatic attraction between oppositely charged ions What is the charge of an ion from group 1? - Answer - +1 What is the charge of an ion from group 2? - Answer - +2 What is the charge of an ion from group 6? - Answer - -2 What is the charge of an ion from group 7? - Answer - -1 Explain how atoms of sodium react with atoms of chlorine - Answer - Na loses its 2s1 electron gaining a +ve charge. Cl gains an electron in the 3p subshell gaining a -ve charge. The opposite charges attract to form NaCl Why do ionic bonds have such high melting points? - Answer - Each +ve ion is surrounded by 6 -ve ions and vice versa. Strong electrostatic attraction in every direction. Requires a large amount of energy to break State two factors that affect the strength of an ionic bond - Answer - Size of ion and charge on ion When can ionic substances conduct electricity? - Answer - When molten or in aqueous solution Describe the properties of ionic compounds - Answer - Conduct electricity when molten or aqueous solution High melting/boiling points Usually solubl