3.3 The Mole & the Avogadro Constant
1. Magnesium nitride and water react to produce a precipitate of magnesium hydroxide and ammonia gas.
Mg3N2 + 6 H2O → 3 Mg(OH)2 + 2 NH3
How much magnesium nitride is needed to produce 87 g of the precipitate in excess water?
Ai এর মাধ্যমে
১০ লক্ষ+ প্রশ্ন ডাটাবেজ
প্র্যাকটিস এর মাধ্যমে নিজেকে তৈরি করে ফেলো
উত্তর দিবে তোমার বই থেকে ও তোমার মত করে।
সারা দেশের শিক্ষার্থীদের মধ্যে নিজের অবস্থান যাচাই
Iron(III) sulphate decomposes when heated. Calculate the mass of iron(III) oxide formed and the volume of sulphur trioxide produced when 10.0 g of iron(III) sulphate was heated. Mass of one mole of Fe2(SO4)3 is 400 g.
Fe2(SO4)3 (s)→ Fe2O3 (s) + 3SO3 (g)
Number of moles of Fe2(SO4)3 =
Number of moles of Fe2O3 formed =
Mass of iron(III) oxide formed in g =
Number of moles of SO3 produced =
Volume of sulphur trioxide at r.t.p. in dm3 =
[5]
This question has 3 part(s).
This question has 3 part(s).
Sulphur dioxide is easily oxidised in the presence of water.
SO2 + 2H2O – 2e– → SO42– + 4H+
i) What colour change would be observed when an excess of aqueous sulphur dioxide is added to an acidic solution of potassium manganate(VII)?
[2]
ii) To aqueous sulphur dioxide, acidified barium chloride solution is added. The mixture remains clear. When bromine is added, a thick white precipitate forms. What is the white precipitate? Explain why it forms.
[3]
