OCR 2023 GCSE CHEMISTRY B TWENTY FIRST CENTURY SCIENCE J258/03: BREADTH IN CHEMISTRY (HIGHER TIER) QUESTION PAPER & MARK SCHEME (MERGED)

2 © OCR 2023 1 Argon forms 1% of the air and is unreactive. Argon is used as a replacement for nitrogen when nitrogen is too reactive. (a) Argon is unreactive because it is in Group 0 of the Periodic Table. State one other property of argon. .............................................................................................................................................. [1] (b) Chlorine is very reactive. Argon is unreactive. Explain how the reactivity of these two elements are related to the arrangement of electrons in their atoms. ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... .............................................................................................................................................. [2] (c) An element X has two electron shells with one electron in its outer shell. (i) Which statements about X are true, and which are false? Tick () one box in each row. True False X is a metal. X is in the first period of the Periodic Table. X forms X – ions. X loses one electron when it reacts. [2] (ii) Name one element that is more reactive than element X. ...................................................................................................................................... [1] 3 © OCR 2023 Turn over (d) An argon atom has a mass number of 40. Calculate the number of neutrons in its nucleus. Use the Periodic Table. Number of neutrons = ..