Muscular organ that pumps blood throughout the body
Answer:
Ans. C. physical change
Explanation:
Physical: boiling and melting are physical changes. When water boils no bonds are broken or formed
Chemical reaction: PCl₅ → PCl₃ + Cl₂.
n(PCl₅) = 0,366 mol.
V(PCl₅) = 4,45 L.
c(PCl₅) = n(PCl₅) ÷ V(PCl₅).
c(PCl₅) = 0,366 mol ÷ 4,45 L.
c(PCl₅) = 0,082 mol/L.
Kc = 1,80.
[PCl₃] = [Cl₂] = x.
Kc = [PCl₃] · [Cl₂] ÷ [PCl₅].
1,80 = x² ÷ (0,082 mol/L - x).
Solve quadratic eqaution: x = [PCl₃] = 0,078 mol/L.
[PCl₅] = 0,082 mol/L - 0,078 mol/L.
[PCl₅] = 0,004 mol/L.
Answer: 16.7 gallon
Explanation:
Given: The car can drive 30.3 miles when 1 gallon of gasoline is used.
Distance covered = 506.3 miles
Thus for 30.3 miles, the amount of gasoline used= 1 gallon
For 506.3 miles, the amount of gasoline used=
Thus the amount of gasoline used is 16.7 gallons.
Answer:
1. Percentage by weight = 0.5023 = 50.23 %
2. molar fraction =0.153
Explanation:
We know that
Molar mass of HClO4 = 100.46 g/mol
So the mass of 5 Moles= 5 x 100.46
Mass (m)= 5 x 100.46 = 502.3 g
Lets assume that aqueous solution of HClO4 and the density of solution is equal to density of water.
Given that concentration HClO4 is 5 M it means that it have 5 moles of HClO4 in 1000 ml.
We know that
Mass = density x volume
Mass of 1000 ml solution = 1 x 1000 =1000 ( density = 1 gm/ml)
m'=1000 g
1.
Percentage by weight = 502.3 /1000
Percentage by weight = 0.5023 = 50.23 %
2.
We know that
molar mass of water = 18 g/mol
mass of water in 1000 ml = 1000 - 502.3 g=497.9 g
So moles of water = 497.7 /18 mole
moles of water = 27.65 moles
So molar fraction = 5/(5+27.65)
molar fraction =0.153
