Answer:
0.0827M of H₂SO₃
Explanation:
LiOH reacts with H₂SO₃ to produce water and Li₂SO₃, thus:
2LiOH + H₂SO₃ → 2H₂O + Li₂SO₃
<em>Where 2 moles of lithium hydroxide react with 1 mole of sulfurous acid.</em>
As the chemist requires 22.14mL = 0.02214L of a 0.210M solution to neutralize the acid, moles of LiOH are:
0.02214L × (0.210mol / L) =<em>0.004649 moles of LiOH</em>.
As 2 moles of LiOH react with 1 mole of H₂SO₃, moles of H₂SO₃ are:
0.004649 moles of LiOH ₓ (1 mole H₂SO₃ / 2 mol LiOH) =
<em>0.002325 moles of H₂SO₃</em>
These moles are present in 28.10mL = 0.02810L. Thus, molar concentration of the acid is:
0.002325 moles H₂SO₃ / 0.02810L = <em>0.0827M of H₂SO₃</em>
Answer:
Color Changes. A change in color often indicates a chemical change.
Temperature Changes. Changes in temperature might also indicate a chemical change has occurred.
Precipitates. The formation of a precipitate is a sign that a chemical change has occurred.
Light Emission.
Gas Production.
Explanation:
Surface of a sphere=4πr²
volume of a sphere=(4/3)πr³
Data:
surface area =432 m²
volume=864 m³
ratio of surface area to volume=surface area / volume
ratio=432 / 864 =0.5
Answer. The ratio would be 0.5
The molar mass of calcium carbonate is 100 mg/mmol, so the
number of moles is:
moles CaCO3 = 500 mg / (100 mg/mmol) = 5 mmol
We see that there is 1 mole of Ca per 1 mole of CaCO3,
therefore:
<span>mass Ca = 5 mmol * (40.08 mg/mmol) = 200.22 mg</span>