The mass percent of sulfurous acid in the new solution : 38.9%
<h3>Further explanation</h3>
<em>In a container you have 800 g of a 35% by mass solution of sulfurous acid, from which 80 ml of water evaporates. What is the mass percent of sulfurous acid in the new solution? data: density of water is 1g / ml.</em>
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solution 1
composition :


solution 2(new solution)
composition :

- Total mass of new solution after water evaporated

- %mass of acid in a new solution

Standard temperature and pressure (STP) means a temperature of 0°c and a pressure of 1 atmosphere (atm). The molar gas volume is used to convert between the number of moles of a gas and the volume of the gas at STP. One mole of a gas occupies a volume of 22400 cm³ or 22.4 liters at STP according to the molar gas volume.
The pH of a solution is 9.02.
c(HCN) = 1.25 M; concentration of the cyanide acid
n(NaCN) = 1.37 mol; amount of the salt
V = 1.699 l; volume of the solution
c(NaCN) = 1.37 mol ÷ 1.699 l
c(NaCN) = 0.806 M; concentration of the salt
Ka = 6.2 × 10⁻¹⁰; acid constant
pKa = -logKa
pKa = - log (6.2 × 10⁻¹⁰)
pKa = 9.21
Henderson–Hasselbalch equation for the buffer solution:
pH = pKa + log(cs/ck)
pH = pKa + log(cs/ck)
pH = 9.21 + log (0.806M/1.25M)
pH = 9.21 - 0.19
pH = 9.02; potential of hydrogen
More about buffer: brainly.com/question/4177791
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Answer:
- 0.99 °C ≅ - 1.0 °C.
Explanation:
- We can solve this problem using the relation:
<em>ΔTf = (Kf)(m),</em>
where, ΔTf is the depression in the freezing point.
Kf is the molal freezing point depression constant of water = -1.86 °C/m,
m is the molality of the solution (m = moles of solute / kg of solvent = (23.5 g / 180.156 g/mol)/(0.245 kg) = 0.53 m.
<em>∴ ΔTf = (Kf)(m)</em> = (-1.86 °C/m)(0.53 m) =<em> - 0.99 °C ≅ - 1.0 °C.</em>
Answer:
Mass = 99.8 g
Explanation:
Given data:
Mass of potassium nitride = ?
Mass of nitrogen produced = 10.65 g
Solution:
Chemical equation:
2K₃N→ 6K + N₂
Moles of nitrogen:
Number of moles = mass/ molar mass
Number of moles = 10.65 g / 28 g/mol
Number of moles = 0.38 mol
Now we will compare the moles of nitrogen with potassium nitride.
N₂ ; K₃N
1 : 2
0.38 : 2×0.38 =0.76
Mass of potassium nitride:
Mass = molar mass × number of moles
Mass = 131.3 g/mol × 0.76 mol
Mass = 99.8 g