BTEC Applied Science Unit 1 Chemistry Exam Questions With Accurate Answers.

BTEC Applied Science Unit 1 Chemistry Exam Questions With Accurate Answers. How many electrons can an s subshell hold? - answer2 How many electrons can a p subshell hold? - answer6 How many electrons can a d subshell hold? - answer10 Which subshells are available in the first energy level? - answers Which subshells are available in the second energy level? - answers and p Which subshells are available in the third energy level? - answers, p and d What is Hund's rule? - answerOrbitals must all be singly filled before they can be doubly occupied Which elements do not fill the 4s subshell before the 3d subshell? - answerCopper and chromium Define the term ionic bond - answerThe 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 - answerNa 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? - answerEach +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 - answerSize of ion and charge on ion When can ionic substances conduct electricity? - answerWhen molten or in aqueous solution Describe the properties of ionic compounds - answerConduct electricity when molten or aqueous solution High melting/boiling points Usually soluble in water Define the term covalent bond - answerA shared pair of electrons Which metals lose electrons from the 4s subshell before the 3d subshell? - answerTransition metals Why do metals have such high melting points? - answerStrong force of attraction between positive ions and delocalised electrons. This requires a large amount of energy to overcome. State the two factors that affect the strength of metallic bonding - answerSize of ion Charge on ion Explain how the charge on metal ions affects the strength of the metallic bond - answerThe larger the +ve charge the greater the attraction between the nucleus and the delocalised electrons Explain how the size of the metal ions affects the strength of the metallic bond - answerThe smaller the +ve ion the closer the nucleus is to the delocalised electrons creating a greater attraction Explain why metals conduct electricity - answerThe delocalised electrons 'carry' charge. Current flows because of this. Explain why metals conduct heat - answerParticles are paced tightly so kinetic energy is passed from ion to ion. The delocalised electrons also enable heat to be passed. Explain why metals are ductile and malleable - answerThe lattice structure allows layers of metal ions to slide over each other without disrupting bonding Name the 3 forces between molecules - answerVan der Waals Permanent dipole-dipole Hydrogen bonds