Answer:
The mass percent of a solution of 7.6 grams sucrose in 83.4 grams of water is 8.351 %.
Explanation:
Given,
Mass of Sucrose = 7.6 grams
Mass of Water = 83.4 grams
In this solution, Sucrose is solute and water is the solvent.
Mass percent of a solution can be calculated using the formula,
Mass percent = (Mass of Solute/Mass of Solution)(100)
As sucrose is solute, mass of solute = 7.6 grams
As the solution contains both Sucrose and Water,
Mass of solution = 7.6 grams + 83.4 grams = 91 grams
Substituting the values, Mass percent = (7.6/91)(100) = 8.351 %.
The control is necessary to make sure that you can tell the difference between the regular, non changed experiment, and the change that happens.
Basically, the control helps you to measure, or observe, the difference in experiments.
And example would be using pills, or flavor water, to see how it affects people.
The control would be the group that either doesn't receive pills or water. This is basically to see how it is normally. The norm.
The first option Forsure .
Answer is: the freezing point of the solution of sucrose is -0.435°C.
m(H₂O) = 100 g ÷ 1000 g/kg = 0.1 kg.
m(C₁₂H₂₂O₁₁) = 8.0 g.
n(C₁₂H₂₂O₁₁) = m(C₁₂H₂₂O₁₁) ÷ M(C₁₂H₂₂O₁₁).
n(C₁₂H₂₂O₁₁) = 8.0 g ÷ 342.3 g/mol.
n(C₁₂H₂₂O₁₁) = 0.0233 mol.
b(solution) = n(C₁₂H₂₂O₁₁) ÷ m(H₂O).
b(solution) = 0.0233 mol ÷ 0.1 kg.
b(solution) = 0.233 m.
ΔT = b(solution) · Kf(H₂O).
ΔT = 0.233 m · 1.86°C/m.
ΔT = 0.435°C.
Tb = 0°C - 0.435°C = -0.435°C.
The depletion of natural resources, the use of chemical and fuel in factories that increased air and water pollution , and increased the use of fossil fuels.