☰ Contents · Chemistry

Water hardness. Practical work 2

Lessons 25–26 · 2 lessons · I.R. Asqarov, K. G‘opirov, N.X. To‘xtaboyev. Chemistry Grade 9, revised 4th edition. “O‘zbekiston” NMIU, Tashkent, 2019
Answers are for parents and teachers.
1
What forms when Mg(HCO₃)₂ is boiled? Write the equation.
2
How many grams of Na₂CO₃ are needed to remove 136 g of CaSO₄? (M(CaSO₄) = 136, M(Na₂CO₃) = 106)
3
Write a plan to identify the solid salts K₂SO₄, Na₂CO₃ and MgCO₃.
4
Write the molecular, full ionic and net ionic equations of CaCO₃ + 2HCl.
5
Ask an adult about scale in a kettle or pot at home and write its cause with a chemical equation.