(a)(i) List two reactants for the laboratory preparation of ammonia
(ii) State three physical properties of ammonia
(iii) Describe in outline, the manufacture of ammonia by the Haber process.
(b) Write an equation in each case to show the:
(i) reaction between ammonia gas and heated copper (II) oxide
(ii) action of heat on ammonium trioxocarbonate (IV)
(c)(i) Which industrial process is used for convey ammonia to trioxonitrate (V) acid?
(ii) Give the reason why electropositive metals do not generally are off hydrogen with dilute trioxonitrate (V) acid
(d) Give one example in each case, to show how trioxonitrate (V) acid reacts generally with: (i) bases (ii) non-metals.
(a)(i) Two reactants for laboratory preparation of ammonia: an ammonium salt (e.g. ammonium chloride, NH4Cl) and a base (e.g. calcium hydroxide, slaked lime).
(ii) Three physical properties of ammonia: colourless gas; pungent (choking) smell; less dense than air; very soluble in water.
(iii) Haber process: Nitrogen (from air) and hydrogen (from natural gas/water) are mixed in the ratio 1 : 3 by volume and passed over a finely divided iron catalyst at about 450°C and a pressure of about 200-250 atm:
N2(g) + 3H2(g) ⇌ 2NH3(g)
The ammonia is cooled and liquefied, and the unreacted gases are recycled.
(b)(i) 3CuO + 2NH3 → 3Cu + N2 + 3H2O
(ii) (NH4)2CO3 → 2NH3 + H2O + CO2
(c)(i) Ammonia is converted to trioxonitrate(V) acid by the Ostwald process.
(ii) Electropositive metals do not liberate hydrogen with dilute HNO3 because HNO3 is a strong oxidizing agent: it oxidizes any hydrogen formed to water while it is itself reduced to oxides of nitrogen (NO or NO2), so oxides of nitrogen are evolved instead of hydrogen.
(d)(i) With bases (neutralization): HNO3 + NaOH → NaNO3 + H2O.
(ii) With non-metals (oxidation): C + 4HNO3 → CO2 + 4NO2 + 2H2O.
(a)(i) Two reactants for laboratory preparation of ammonia: an ammonium salt (e.g. ammonium chloride, NH4Cl) and a base (e.g. calcium hydroxide, slaked lime).
(ii) Three physical properties of ammonia: colourless gas; pungent (choking) smell; less dense than air; very soluble in water.
(iii) Haber process: Nitrogen (from air) and hydrogen (from natural gas/water) are mixed in the ratio 1 : 3 by volume and passed over a finely divided iron catalyst at about 450°C and a pressure of about 200-250 atm:
N2(g) + 3H2(g) ⇌ 2NH3(g)
The ammonia is cooled and liquefied, and the unreacted gases are recycled.
(b)(i) 3CuO + 2NH3 → 3Cu + N2 + 3H2O
(ii) (NH4)2CO3 → 2NH3 + H2O + CO2
(c)(i) Ammonia is converted to trioxonitrate(V) acid by the Ostwald process.
(ii) Electropositive metals do not liberate hydrogen with dilute HNO3 because HNO3 is a strong oxidizing agent: it oxidizes any hydrogen formed to water while it is itself reduced to oxides of nitrogen (NO or NO2), so oxides of nitrogen are evolved instead of hydrogen.
(d)(i) With bases (neutralization): HNO3 + NaOH → NaNO3 + H2O.
(ii) With non-metals (oxidation): C + 4HNO3 → CO2 + 4NO2 + 2H2O.
