Alkalis are substances that turn universal indicator paper blue or purple.
Which ion is released in aqueous solution that makes a substance alkaline?
Calcium hydroxide, Ca(OH)2\text{Ca(OH)}_2Ca(OH)2, is an alkali. It neutralizes hydrochloric acid, HCl\text{HCl}HCl. This reaction produces a salt called calcium chloride, CaCl2\text{CaCl}_2CaCl2, and water.
Complete the balanced symbol equation for this reaction:
Ca(OH)2+……HCl→CaCl2+……H2O\text{Ca(OH)}_2 + \dots\dots\text{HCl} \rightarrow \text{CaCl}_2 + \dots\dots\text{H}_2\text{O}Ca(OH)2+……HCl→CaCl2+……H2O
During a neutralization reaction, a student wants to obtain highly precise and continuous pH readings instead of using universal indicator paper.
Suggest a digital piece of equipment that the student could use to measure the pH of the solution.
Describe how to prepare and use the equipment suggested in (b)(i) to ensure accurate and reliable measurements.
Sodium sulfate, Na2SO4\text{Na}_2\text{SO}_4Na2SO4, is a salt used in manufacturing laundry detergent flakes.
A student wants to make a pure, dry sample of sodium sulfate by the neutralization of an acid with an alkali.
Describe how to prepare a pure, dry sample of sodium sulfate in a laboratory. Your explanation should include the names of the reactants used, how to ensure you obtain a neutral solution, and how to get the dry salt crystals.