Answer:
Explanation:
Just as context, write the chemical equation and the mole ratios
1) <u>Balanced chemical equation</u>:
- CuO (s) + H₂SO₄ (aq) → CuSO₄ (aq) + H₂O (l)
2) <u>Therotetical (stoichiometric) mole ratios</u>:
- 1 mol CuO : 1 mol H₂SO₄ : 1 mol CuSO₄ : 1 mol H₂O
You can calculate the percent yield from the amount of CuSO₄ obtained and the theoretical yield
3) <u>Percent yield</u>
Percent yield = (actual yield / theoretical yield)×100
- Theoretical yiedl (given): 3.19 moles CuSO₄
- Actual yield (given): 2.50 moles CuSO₄
Substitute the values in the formula:
- Percent yield = (2.50 moles CuSO₄ / 3.19 moles CuSO₄)×100 = 78.4%
<span>n this order, Ď=1.8gmL, cm=0.5, and mole fraction = 0.9
First, let's start with wt%, which is the symbol for weight percent. 98wt% means that for every 100g of solution, 98g represent sulphuric acid, H2SO4.
We know that 1dm3=1L, so H2SO4's molarity is
C=nV=18.0moles1.0L=18M
In order to determine sulphuric acid solution's density, we need to find its mass; H2SO4's molar mass is 98.0gmol, so
18.0moles1Lâ‹…98.0g1mole=1764g1L
Since we've determined that we have 1764g of H2SO4 in 1L, we'll use the wt% to determine the mass of the solution
98.0wt%=98g.H2SO4100.0g.solution=1764gmasssolution→
masssolution=1764gâ‹…100.0g98g=1800g
Therefore, 1L of 98wt% H2SO4 solution will have a density of
Ď=mV=1800g1.0â‹…103mL=1.8gmL
H2SO4's molality, which is defined as the number of moles of solute divided by the mass in kg of the solvent; assuming the solvent is water, this will turn out to be
cm=nH2SO4masssolvent=18moles(1800â’1764)â‹…10â’3kg=0.5m
Since mole fraction is defined as the number of moles of one substance divided by the total number of moles in the solution, and knowing the water's molar mass is 18gmol, we could determine that
100g.solutionâ‹…98g100gâ‹…1mole98g=1 mole H2SO4
100g.solutionâ‹…(100â’98)g100gâ‹…1mole18g=0.11 moles H2O
So, H2SO4's mole fraction is
molefractionH2SO4=11+0.11=0.9</span>
Answer:
Rate of forward reaction will increase.
Explanation:
Effect of change in reaction condition on equilibrium is explained by Le Chatelier's principle. According to this principle,
If an equilibrium condition of a dynamic reversible reaction is disturbed by changing concentration, temperature, pressure, volume, etc, then reaction will move will in a direction which counteract the change.
In the given reaction,
A + B ⇌ C + D
If concentration of A is increase, then reaction will move in a direction which decreases the concentration of A to reestablish the equilibrium.
As concentration A decreases in forward direction, therefore, rate of forward reaction will increase.
Answer: Option (b) is the correct answer.
Explanation:
A statement which states a scientifically acceptable general principle that is experimentally tested or verified is defined as a theory.
A theory is the sum of a number of observations which are tested in order to get the true result so that a statement can be framed.
Thus, we can conclude that out of the given options, a theory is a well-tested explanation for a broad set of observations.
D. infrared waves.
The infrared waves are hard to detect, so it is hard to detect where the soldiers are at night