Give the meaning of the term diatomic.
Work out the numbers of protons, neutrons and electrons in the chloride ion shown, $^{37}_{17}\text{Cl}^-.$
State what is meant by exothermic.
Fig. 4.1 gives an incomplete reaction pathway diagram for the reaction between chlorine and hydrogen. Finish Fig. 4.1 by adding these formulae to the diagram: Cl$_2$ + H$_2$, 2HCl.
Explain how Fig. 4.1 indicates that the reaction is exothermic.
State the colour of the solution.
Complete the word equation for this reaction.\n\nhydrochloric acid + sodium hydroxide → [BLANK] + [BLANK]
Sodium hydroxide is an alkali. Write the formula of the ion found in all alkalis.
Label Fig. 4.2 to show the anode and the electrolyte.
Name the products and describe the observations at the positive and negative electrodes.