Which of the following physical processes involves the breaking of strong covalent bonds?
Sublimation of dry ice, CO2(s)→CO2(g)\text{CO}_2(\text{s}) \rightarrow \text{CO}_2(\text{g})CO2(s)→CO2(g)
Melting of quartz, SiO2(s)→SiO2(l)\text{SiO}_2(\text{s}) \rightarrow \text{SiO}_2(\text{l})SiO2(s)→SiO2(l)
Boiling of water, H2O(l)→H2O(g)\text{H}_2\text{O}(\text{l}) \rightarrow \text{H}_2\text{O}(\text{g})H2O(l)→H2O(g)
Melting of sodium chloride, NaCl(s)→NaCl(l)\text{NaCl}(\text{s}) \rightarrow \text{NaCl}(\text{l})NaCl(s)→NaCl(l)
74 exam-style questions on OCR GCSE Chemistry Bonding. Each one has a worked solution and a mark scheme showing where the marks go.