Is ionic equation . nitric acid + solid aluminium = hydroxide.
Answer:
Explanation:
<u>1) Chemical equation (given)</u>
<u>2) Theoretical yield</u>
<u>a) Convert mass of NaHCO₃ to moles:</u>
- n = mass in grams / molar mass
- molar mass = 84.007 g/mol
- n = 2.36 g / 84.007 g/mol = 0.02809 mol
<u>b) Mole ratio:</u>
- 2 mol NaHCO₃ : 1 mol H₂CO₃
<u>c) Proportionality:</u>
- 2 mol NaHCO₃ / mol H₂CO₃ = 0.02809 mol NaHCO₃ / x
⇒ x = 0.2809 / 2 mol H₂CO₃ = 0.01405 mol H₂CO₃
<u>3) Actual yield</u>
<u>a) Mass balance</u>: 2.36 g - 1.57 g = 0.79 g
<u>b) Convert 0.79 g of carbonic acid to number of moles</u>:
- n = mass in grams / molar mass
- n = 0.79 g / 62.03 g/mol = 0.01274 mol
<u>4) Percentage yield, y (%)</u>
- y (%) = actual yield / theoretical yield × 100
- y (%) = 0.1274 mol / 0.1405 mol × 100 = 90.68%
The answer must show 3 significant figures, so y(%) = 90.7%.
The awnser is A :)
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Answer: In this case, you can estimate that the solubility of potassium nitrate in water at
60
∘
C
is equal to about
solubility
≈
110 g / 100 mL water
−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−
This tells you that a saturated solution of potassium nitrate will hold about
110 g
of dissolved salt, i.e. of dissociated salt, per
100 mL
of water at
60
∘
C
.