Answer:
0.0986M is the concentration of the Na₂S₂O₃ solution
Explanation:
Potassium iodate, KIO₃, reacts with sodium thiosulfate, Na₂S₂O₃, as follows:
KIO₃ + 6Na₂S₂O₃ +5KI + 3H₂SO₄ → 3H₂O + 3K₂SO₄ + 3Na₂S₄O₆ + 6NaI
To solve this question we must find the moles of sodium thiosulfate that reacts as follows:
Moles KIO₃:
0.0250L * (0.0100mol / L) = 2.5x10⁻⁴moles KIO₃
Moles Na₂S₂O₃:
2.5x10⁻⁴moles KIO₃ * (6mol Na₂S₂O₃ / 1mol KIO₃) = 1.5x10⁻³ moles Na₂S₂O₃
Molar concentration:
1.5x10⁻³ moles Na₂S₂O₃ / 0.01521L =
0.0986M is the concentration of the Na₂S₂O₃ solutionConsider the Fischer ester synthesis of methyl benzoate from benzoic acid and methanol in the presence of sulfuric acid as a catalyst. A reaction was performed in which 3.8 g of benzoic acid was reacted with excess methanol to make 2.0 g of methyl benzoate. Calculate the theoretical yield and percent yield for this reaction.
Answer:
48.8%
Explanation:
The reaction has a 1:1 mole ratio so;
Number of moles of benzoic acid reacted = mass/molar mass = 3.8 g/122.12 g/mol = 0.03 moles
So;
0.03 moles of methyl benzoate is formed in the reaction
Mass of methyl benzoate formed = 0.03 moles * 136.15 g/mol = 4.1 g
percent yield = actual yield/theoretical yield * 100/1
percent yield = 2.0 g/4.1 g * 100 = 48.8%
2 moles KCl + 3 moles O2 → 2moles KCIO3
Calculate the number of particles of each substance based on the number of moles from the balanced equation
Answer:
KCl ⇒ 1.205x10²⁴ molecules
O₂ ⇒ 1.807x10²⁴ molecules
KClO₃ ⇒ 1.205x10²⁴ molecules
Explanation:
In order to calculate the number of particles from the number of moles, we have to use Avogadro's number, which states the number of particles in one mol:
In 1 mol there are 6.023x10²³ particles (ions, molecules or atoms).So now we multiply the number of moles of each substance by Avogadro's number:
KCl ⇒ 2 mol * 6.023x10²³ molecules/mol = 1.205x10²⁴ moleculesO₂ ⇒ 3 mol * 6.023x10²³ molecules/mol = 1.807x10²⁴ moleculesKClO₃ ⇒ 2 mol * 6.023x10²³ molecules/mol = 1.205x10²⁴ molecules