F.4 chem acid and alkali

Which of the following substances will not react with sodium hydroxide solution?
A. Ammonium sulphate
B. Iron (III) nitrate
C. Nitric acid
D. Copper

The answer is D.

A. will react. 會進行反應。
Like other ammonium salts, ammonium sulphate reacts (under heating) with sodium hydroxide solution to give ammonia gas.
硫酸銨與其它銨鹽相似，與氫氧化鈉溶液（在加熱下）反應，生成氨氣。
(NH4)2SO4(aq) + 2NaOH(aq) → Na2SO4(aq) + 2NH3(g) + H2O(l)
or: NH4^+(aq) + OH^-(aq) → NH3(g) + H2O(l)

B. will react.
Like other solutions of iron(III) salts, iron(III) nitrate solution reacts with sodium hydroxide solution to give iron(III) hydroxide precipitate.
硝酸鐵(III)鹽與其他鐵(III)鹽相似，與氫氧化鈉溶液反應，生成氫氧化鐵(III)沉澱。
Fe(NO3)3(aq) + 3NaOH(aq) → Fe(OH)3(s) + 3NaNO3(aq)
or: Fe^3+(aq) + 3OH^-(aq) → Fe(OH)3(s)

C. will react.
Sodium hydroxide is an alkali, while nitric acid is an acid. Neutralization occurs.
氫氧化鈉是鹼，而硝酸是酸。發生中和作用。
HNO3(aq) + NaOH(aq) → NaNO3(aq) + H2O(l)
or: H^+(aq) + OH^-(aq) → H2O(l)

D. will not react.
Copper does not react with alkalis.
銅與鹼不起反應。


Also, is copper can't react with dilute acid to give out hydrogen due to copper can't displace acid ?

Yes, the reducing power of copper is weaker than hydrogen. Therefore, copper cannot displace hydrogen for acids.
對，銅的還原能力較氫低。因此，銅不能從酸中置換氫。

因為alkali同acid5一樣,alkali係有hydroxide去react,而acid就係有hydrogen去react.但係alkali 5同acid有hydrogen,所以copper react 5到.其實無論係其他iron ar,calcium都5會同alkali react ga.所以一定會係d.
copper喺dilute acid 5會有反應,因為copper個reactivity seires太低la.hydrogen喺reactivity seires係高過copper,所以displace 5到.但係concentrated acid就react到,因為concentrated acid可以oxidize copper.