Define and give an example each of the following: i. Acid salt ii. Basicity of an acid iii. Deliquescent substance Iv. Double salt V. Efflorescent substances vi. Hydroscopic substance. – NABTEB QUESTION

Solution:

i. Acid salt is a compound made up of a metallic cation and non-metallic anion which dissolves in water to produce a weak acid E.g. KHS04, Ca (HS04)2.

ii. The basicity of acid is the number of hydrogen ions, 1 molecule of it can produce in solution, or molten state.
e.g., Basicity of HNO3 = 1, H2SO4 = 2, H3PO4 = 3 , HCl = 1.

iii. Deliquescent substance is that matter which absorbs water moisture, from the atmosphere to form a solution at the end.

Examples include:

• Sodium hydroxide pellets.
• Iron (II) Chloride crystals
• Calcium chloride (fused)
• Magnesium chloride
• Phosphorous (v) oxide

(iv) Double salt is that which ionized to produce three different types of ions in solution E.g. NaNH4SO4, KMnO4

(v) Efflorescent substance is that crystal that forms one or more molecules of water of crystallization when exposed to the atmosphere. Examples include. Na2CO3.10H2O, CUSO4.5H20, MgSO4.7H20.

(Vi) Hydroscopic substance is the substances which absorb moisture from the atmosphere but does not dissolves in it.

Examples include:

• Sodium trioxonitrate (v)
• Copper (II) oxide
• Calcium oxide
• Conc. H2SO4.