☰ Year plan · Chemistry

Cations, and the idea of a titration

Week 8 · Chapter 2 (C): detecting cations (six analytical groups: copper(II), aluminium, iron(II), iron(III), calcium) and the start of quantitative analysis: titration, standard solutions, end point and indicators · 3 lessons
Answers are for parents and teachers.
1
Complete and balance: Cu(NO₃)₂ + H₂S → ? Name the colour of the solid (paper only).
2
Complete and balance: Fe(NO₃)₃ + NaOH → ? Give the colour of the precipitate.
3
Both Al³⁺ and Fe²⁺ give a white precipitate with ammonium hydroxide. Which extra test separates them?
4
What volume of 0.100 M HCl just neutralises 25.0 mL of 0.0400 M NaOH, using HCl + NaOH → NaCl + H₂O?
5
In the kitchen model, cup A needed 9 drops of vinegar. Cup B has three times as much baking soda. About how many drops should cup B need? Say that the numbers are invented.