State which symbol or formula represents a compound made in respiration.
State which symbol or formula represents an ion that produces a lilac flame test colour.
State which symbol or formula represents a gas that makes up 21% of clean, dry air.
State which symbol or formula represents an element with a radioactive isotope used as an energy source.
State which symbol or formula represents an ion formed when an atom gains an electron.
Fill in the table to give the relative masses of a proton, a neutron and an electron.
Select the two correct statements about carbon dioxide. Tick (✓) two boxes. Carbon dioxide is made up of two elements mixed together. Carbon dioxide is an acidic oxide. Carbon dioxide contains ionic bonding. Carbon dioxide forms a giant covalent structure. A molecule of carbon dioxide contains three atoms.