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Chemical Reactions — CHEMISTRY STD 8 — Question

ICSE BoardEnglish MediumSTD 8CHEMISTRYChemical Reactions4 Marks
Question
Give two examples each of the following oxides $–$
$(a)$ Acidic oxides
$(b)$ Basic oxides
$(c)$ Amphoteric oxides
$(d)$ Neutral
oxides. State which of the following oxides Le. $(a)$ to $(d)$
$(i)$ React with water to give a base
$(ii)$ React with a base to give salt $\&$ water
$(iii)$ React with acids $\&$ bases to give salt $\&$ water.
✓

Answer

$(a)$ Acidic oxides : Non$-$metallic oxides are acidic oxides.
$1.\ce{ SO_2}$
$2. \ce{CO_2}$
$3. \ce{NO_2}$ are acidic oxides.
$(b)$ Basic oxides : Metallic oxides are basic oxides.
$1. \ce{Na_2O}$
$2. \ce{K_2O}$
$3. \ce{CaO}$ are basic oxides.
$(c)$ Amphoteric oxides : Oxides of metals like $\ce{Zn , Pb , A 1}$ are amphoteric oxides.
$1. \ce{ZnO}$
$2. \ce{PbO}$
$3. \ce{Al_2O_3}$ are amphoteric oxides.
$(d)$ Neutral oxides: Oxides like $\ce{(i) NO (ii) CO (iii) N_2O}$ are neutral oxides.
$1.$ Basic oxides react with water to give bases.
$2.$ Acidic oxide reacts with base to give salt and water.
$3.$ Amphoteric oxide reacts with acids and bases to give salt and water.

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