In neutralisation reactions with hydroxide ions to indicator to measure the neutralisation reactions between an acid and an form approximate pH of a solution. provides opportunities to alkali, hydrogen ions with cover the measurement WS 3.2 hydroxide ions to produce of pH (biology AT 1 and Use the pH scale to identify water. chemistry AT 3). acidic or alkaline solutions. 4.7.3.5 (HT only) Use and explain the 1 Explain the meaning of the Use universal indicator terms dilute and following terms: or a pH probe to A strong acid is completely concentrated (amount measure the pH of ionised in aqueous solution. dilute of substance) and hydrochloric acid, Examples of strong acids are concentrated weak and strong ethanoic acid, sodium hydrochloric, nitric and weak (degree of ionisation) hydroxide and sulfuric acids. strong. in relation to acids. ammonium hydroxide. A weak acid is only partially Explain why strong acids are Be careful to use the Recall that as ionised in aqueous solution. completely ionised in aqueous same concentration of hydrogen ion Examples of weak acids are solutions but a weak acid is each. concentration ethanoic, citric and carbonic only partially ionised. increases by a factor Compare the rate of acids. Recall examples of strong and of ten the pH value of reaction when For a given concentration of weak acids. a solution decreases magnesium is dipped in aqueous solutions, the by a factor of one. hydrochloric acid and Describe neutrality in on stronger an acid, the lower ethanoic acid of the hydrogen ion concentration. Describe neutrality and the pH. same concentration. relative acidity and
In neutralisation reactions between an acid and an alkali, hydrogen ions with hydroxide ions to produce water. with hydroxide ions to form indicator to measure the approximate pH of a solution. WS 3.2 Use the pH scale to identify acidic or alkaline solutions. neutralisation reactions provides opportunities to cover the measurement of pH (biology AT 1 and chemistry AT 3). 4.7.3.5 (HT only) A strong acid is completely ionised in aqueous solution. Examples of strong acids are hydrochloric, nitric and sulfuric acids. A weak acid is only partially ionised in aqueous solution. Examples of weak acids are ethanoic, citric and carbonic acids. For a given concentration of aqueous solutions, the stronger an acid, the lower the pH. Use and explain the terms dilute and concentrated (amount of substance) and weak and strong (degree of ionisation) in relation to acids. Recall that as hydrogen ion concentration increases by a factor of ten the pH value of a solution decreases by a factor of one. Describe neutrality and relative acidity and 1 Explain the meaning of the following terms: dilute concentrated weak strong. Explain why strong acids are completely ionised in aqueous solutions but a weak acid is only partially ionised. Recall examples of strong and weak acids. Describe neutrality in on hydrogen ion concentration. Use universal indicator or a pH probe to measure the pH of hydrochloric acid, ethanoic acid, sodium hydroxide and ammonium hydroxide. Be careful to use the same concentration of each. Compare the rate of reaction when magnesium is dipped in hydrochloric acid and ethanoic acid of the same concentration.