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Question 3
The melting points and boiling points of four substances (A, B, C and D) are shown inthe table below. 3.1 Define the term melting point. (2) 3.2 Explain the difference in melting points of HF and HCâ„“ by referring to theTYPE of intermolecular forces. (4) 3.3 Which ONE of the substances (A, B, C or … Read more
Question 2
2.1 Ammonia NH3(g) and hypochlorous acid HOCâ„“(â„“) are both examples ofcovalent compounds. 2.1.1 Define the term bonding pair. (2) 2.1.2 Draw Lewis structures for the following molecules: (a) NH3 (2)(b) HOCâ„“ (2) 2.1.3 Write down the: (a) Number of bonding pairs in NH3 (1)(b) Number of lone pairs on the oxygen atom in HOCâ„“ (1)(c) … Read more
Question 1
Various options are provided as possible answers to the following questions. Choose the answer and write only the letter (A–D) next to the question numbers (1.1 to 1.10) in the ANSWER BOOK, e.g. 1.11 E. Each question has only ONE correct answer. 1.1 The number of valence electrons in a silicon atom is … A … Read more
Question 11
Given the digits: 3 ; 4 ; 5 ; 6 ; 7 ; 8 and 9 11.1 Calculate how many unique 5-digit codes can be formed using the digits above, if: 11.1.1) The digits may be repeated (2) 11.1.2) The digits may not bc repeated (2) 11.2 How many unique 3-digit codes can be formed … Read more