HNO3+ NaOH = NaNO3 + H2O
n(NaOH)=m/M = 4/40 = 0.1моля
значит n(HNO3)= 0.1 моля
m(HNO3)= n*M = 0.1 * 63 = 6.3 г
w(HNO3)= m(HNO3)/ m(р-ра HNO3)= 6,3 / 200 = 0.0315 или 3,15%
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Na2O + H2O -> 2NaOH
3NaOH + AlCl3 -> Al(OH)3 + 3NaCl
Al(OH)3 + 3HCl -> AlCl3 + 3H2O
AlCl3 + 3KOH -> Al(OH)3 + 3KCl