Page 92 - Chemistry ICSE Class X
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78 ICSE Chemistry – 10
Chlorides
Chlorides are not decomposed by dilute acids. However, concentrated
sulphuric acid decomposes chloride salts forming the sulphate or hydrogen
sulphate salt (depending on the temperature) and hydrogen chloride
[HCl(g)]. This is because hydrochloric acid is more volatile than sulphuric
acid. For example,
< 200°C
NaCl(s) + H SO (l) o NaHSO 4 + HCl(g)
4
2
sodium chloride conc. sulphuric sodium hydrogen hydrogen chloride
acid sulphate (acid salt) (pungent, irritating)
> 200°C
2NaCl(s) + H SO (l) o Na SO (s) + 2HCl(g)
4
2
4
2
conc. sulphuric sodium sulphate
acid (normal salt)
Nitrates
Nitrates are decomposed by conc. sulphuric acid on heating below 200°C
because nitric acid is more volatile than conc. H SO . For example,
2
4
< 200°C
KNO (s) + H SO (l) o KHSO (s) + HNO (g)
3
4
4
3
2
potassium nitrate conc. sulphuric potassium hydrogen nitric acid
acid sulphate (acid salt)
Above 200°C, nitric acid itself decomposes.
ASSIGNMENT 6
Salts, Classification of salts, General properties of salts
ϭ͘ 'ŝǀĞ ƚǁŽ ĞdžĂŵƉůĞƐ ĞĂĐŚ ŽĨ ƚŚĞ ĨŽůůŽǁŝŶŐ͗
;ĂͿ EŽƌŵĂů ƐĂůƚƐ ;ďͿ ĐŝĚ ƐĂůƚƐ ;ĐͿ ĂƐŝĐ ƐĂůƚƐ
Ϯ͘ 'ŝǀĞ ƚŚĞ ŶĂŵĞƐ ĂŶĚ ĨŽƌŵƵůĂĞ ŽĨ ƚŚĞ ĨŽůůŽǁŝŶŐ͗
;ĂͿ ĚŽƵďůĞ ƐĂůƚ ;ďͿ ŵŝdžĞĚ ƐĂůƚ ;ĐͿ ĐŽŵƉůĞdž ƐĂůƚ
ϯ͘ ^ŽĚŝƵŵ ĐĂƌďŽŶĂƚĞ ŝƐ Ă ŶŽƌŵĂů ƐĂůƚ͕ LJĞƚ ŝƚƐ ƐŽůƵƟŽŶ ŝƐ ďĂƐŝĐ͘ 'ŝǀĞ ƌĞĂƐŽŶ͘
ϰ͘ &ƌŽŵ ƚŚĞ ĨŽƌŵƵůĂĞ ŐŝǀĞŶ ďĞůŽǁ͕ ĐŚŽŽƐĞ ŽŶĞ ŝŶ ĞĂĐŚ ĐĂƐĞ͕ ĐŽƌƌĞƐƉŽŶĚŝŶŐ ƚŽ ƚŚĞ ƐĂůƚ ŚĂǀŝŶŐ ƚŚĞ ŐŝǀĞŶ ĚĞƐĐƌŝƉƟŽŶ͘
Ő ů͕ Ƶ K ͕ Ƶ^K ͘ ϱ, K͕ <EK ͕ EĂ ů͕ EĂ,^K ͕ Wď;EK Ϳ ͕ Ŷ K ͕ Ŷ^K ͘ ϳ, O
2
3 2
4
3
3
4
3
2
4
;ĂͿ Ŷ ĂĐŝĚ ƐĂůƚ͘
;ďͿ Ŷ ŝŶƐŽůƵďůĞ ĐŚůŽƌŝĚĞ͘
;ĐͿ dŚĞ ƐĂůƚ ĐŚĂŶŐĞƐ ŝƚƐ ĐŽůŽƵƌ ĨƌŽŵ ďůƵĞ ƚŽ ǁŚŝƚĞ ǁŚĞŶ ƚƌĞĂƚĞĚ ǁŝƚŚ ĐŽŶĐ͘ ƐƵůƉŚƵƌŝĐ ĂĐŝĚ͘
;ĚͿ dŚĞ ƐĂůƚ ĐŚĂŶŐĞƐ ŝƚƐ ĐŽůŽƵƌ ĨƌŽŵ ŐƌĞĞŶ ƚŽ ďůĂĐŬ ŽŶ ŚĞĂƟŶŐ͘
;ĞͿ dŚĞ ƐĂůƚ ŐŝǀĞƐ ŶŝƚƌŽŐĞŶ ĚŝŽdžŝĚĞ ŽŶ ŚĞĂƟŶŐ͘
ϱ ͘ E Ă ŵ Ğ
;ĂͿ ĐŚůŽƌŝĚĞ ǁŚŝĐŚ ŝƐ ŝŶƐŽůƵďůĞ ŝŶ ĐŽůĚ ǁĂƚĞƌ ďƵƚ ĚŝƐƐŽůǀĞƐ ŝŶ ŚŽƚ ǁĂƚĞƌ͘
;ďͿ ĐŚůŽƌŝĚĞ ǁŚŝĐŚ ŝƐ ŝŶƐŽůƵďůĞ ďŽƚŚ ŝŶ ĐŽůĚ ĂŶĚ ŚŽƚ ǁĂƚĞƌ͘
;ĐͿ dǁŽ ŝŶƐŽůƵďůĞ ƐƵůƉŚĂƚĞƐ͘
;ĚͿ dǁŽ ƐĂůƚƐ ǁŚŽƐĞ ƐŽůƵďŝůŝƚLJ ŝŶĐƌĞĂƐĞƐ ǁŝƚŚ Ă ƌŝƐĞ ŝŶ ƚĞŵƉĞƌĂƚƵƌĞ͘
;ĞͿ ƐĂůƚ ǁŚŽƐĞ ƐŽůƵďŝůŝƚLJ ĚĞĐƌĞĂƐĞƐ ǁŝƚŚ Ă ƌŝƐĞ ŝŶ ƚĞŵƉĞƌĂƚƵƌĞ͘
General Methods of Preparation of Soluble Salts
How are water-soluble salts prepared
Water-soluble salts can be prepared by the following general methods:
