Which best describes the scientific method?
2 answers:
You might be interested in
The solution of Sulfuric Acid (H2SO4) has the following mole fractions:
- mole fraction (H2SO4)= 0.034
- mole fraction (H2O)= 0.966
To solve this problem the formula and the procedure that we have to use is:
- n = m / MW
- = ∑ AWT
- mole fraction = moles of A component / total moles of solution
- ρ = m /v
Where:
- m = mass
- n = moles
- MW = molecular weight
- AWT = atomic weight
- ρ = density
- v = volume
Information about the problem:
- m solute (H2SO4) = 17.75 g
- v(solution) = 100 ml
- ρ (solution)= 1.094 g/ml
- AWT (H)= 1 g/mol
- AWT (S) = 32 g/mol
- AWT (O)= 16 g/mol
- mole fraction(H2SO4) = ?
- mole fraction(H2O) = ?
We calculate the moles of the H2SO4 and of the H2O from the Pm:
MW = ∑ AWT
MW (H2SO4)= AWT (H) * 2 + AWT (S) + AWT (O) * 4
MW (H2SO4)= (1 g/mol * 2) + (32,064 g/mol) + (16 g/mol * 4)
MW (H2SO4)= 2 g/mol + 32 g/mol + 64 g/mol
MW (H2SO4)= 98 g/mol
MW (H2O)= AWT (H) * 2 + AWT (O)
MW (H2O)= (1 g/mol * 2) + (16 g/mol)
MW (H2O)= 2 g/mol + 16 g/mol
MW (H2O)= 18 g/mol
Having the Pm we calculate the moles of H2SO4:
n = m / MW
n(H2SO4) = m(H2SO4) / MW (H2SO4)
n(H2SO4) = 17.75 g / 98 g/mol
n(H2SO4) = 0.1811 mol
With the density and the volume of the solution we get the mass:
ρ(solution)= m(solution) /v(solution)
m(solution) = v(solution) * ρ(solution)
m(solution) = 100 ml * 1.094 g/ml
m(solution) = 109.4 g
Having the mass of the solution we calculate the mass of the water in the solution:
m(H2O) = m(solution) - m solute (H2SO4)
m(H2O) = 109.4 g - 17.75 g
m(H2O) = 91.65 g
We calculate the moles of H2O:
n = m / MW
n(H2O) = m(H2O) / MW (H2O)
n(H2O) = 91.65 g / 18 g/mol
n(H2O) = 5.092 mol
We calculate the total moles of solution:
total moles of solution = n(H2SO4) + n(H2O)
total moles of solution = 0.1811 mol + 5.092 mol
total moles of solution = 5.2731 mol
With the moles of solution we can calculate the mole fraction of each component:
mole fraction (H2SO4)= moles of (H2SO4) / total moles of solution
mole fraction (H2SO4)= 0.1811 mol / 5.2731 mol
mole fraction (H2SO4)= 0.034
mole fraction (H2O)= moles of (H2O) / total moles of solution
mole fraction (H2O)= 5.092 mol / 5.2731 mol
mole fraction (H2O)= 0.966
<h3>What is a solution?</h3>In chemistry a solution is known as a homogeneous mixture of two or more components called:
- Solvent
- Solute
Learn more about chemical solution at: brainly.com/question/13182946 and brainly.com/question/25326161
#SPJ4
Answer:
A) = 1.44 kg m², B) moment of inertia must increase
Explanation:
The moment of inertia is defined by
I = ∫ r² dm
For figures with symmetry it is tabulated, in the case of a cylinder the moment of inertia with respect to a vertical axis is
I = ½ m R²
A very useful theorem is the parallel axis theorem that states that the moment of inertia with respect to another axis parallel to the center of mass is
I = + m D²
Let's apply these equations to our case
The moment of inertia is a scalar quantity, so we can add the moment of inertia of the body and both arms
=
+ 2
= ½ M R²
The total mass is 64 kg, 1/8 corresponds to the arms and the rest to the body
M = 7/8 m total
M = 7/8 64
M = 56 kg
The mass of the arms is
m’= 1/8 m total
m’= 1/8 64
m’= 8 kg
As it has two arms the mass of each arm is half
m = ½ m ’
m = 4 kg
The arms are very thin, we will approximate them as a particle
= M D²
Let's write the equation
= ½ M R² + 2 (m D²)
Let's calculate
= ½ 56 0.20² + 2 4 0.20²
= 1.12 + 0.32
= 1.44 kg m²
b) if you separate the arms from the body, the distance D increases quadratically, so the moment of inertia must increase