Answer:
pH = 4.27. Porcentaje de disociación: 0.03%
Explanation:
El pH de un ácido débil, HX, se obtiene haciendo uso de su equilibrio:
HX(aq) ⇄ H⁺(aq) + X⁻(aq)
Donde la constante de equilibrio, Ka, es
Ka = 1.65x10⁻⁸ = [H⁺] [X⁻] / [HX]
Como los iones H⁺ y X⁻ vienen del mismo equilibrio podemos decir:
[H⁺] = [X⁻]
[HX] es:
20g * (1mol/55g) = 0.3636moles / 2.100L = 0.1732M
Reemplazando es Ka:
1.65x10⁻⁸ = [H⁺] [H⁺] / [0.1732M]
2.858x10⁻⁹ = [H⁺]²
5.35x10⁻⁵M = [H⁺]
pH = -log[H⁺]
<h3>pH = 4.27</h3>
El porcentaje de disociacion es [X⁻] / [HX] inicial * 100
Reemplazando
5.35x10⁻⁵M / 0.1732M * 100
<h3>0.03%</h3>
Answer is: the discovery of sub atomic particles like electrons.
J. J. Thomson discovered the electron in 1897.
His "plum pudding" model (1904) suggested: the electrons are embedded in the positive charge.
With this model, he abandoned his earlier hypothesis (the atom was composed of immaterial vortices).
J.J. Thomson placed two oppositely charged electric plates around the cathode ray. He did experiments using different metals as electrode materials and found that the properties of the cathode ray remained constant no matter what cathode material he used.
Tomson concluded that atoms are divisible and that the corpuscles are their building blocks (atoms are made up of smaller particles).
<u>11.35 g</u><u> </u><u>atoms </u><u>of lead are in the sample.</u>
What does density mean?
- The density of an area refers to the quantity of things—which may include people, animals, plants, or objects—there are in it.
- Divide the number of objects by the area's measurement to determine density.
- A country's population density is calculated by dividing its total population by its area, expressed in square kilometers or miles.
We can calculate the volume of the cube by cubing the side of the cube.
Volume of cube = ( 1.000 cm)³
= 1.000 cm³
We can now determine the amount of lead in the cube by multiplying by the density. Because we know we have a 1.000 cubic centimeter and that lead has a density of 11.35 grams per cubic centimeter, we have 11.35 grams of lead.
= ( 1.000 cm³) ( 11.35 
)
= 11.35 g
Learn more about density
brainly.com/question/15164682
#SPJ4
Answer:
11.66 L.
Explanation:
- We can use the general law of ideal gas: <em>PV = nRT.</em>
where, P is the pressure of the gas in atm.
V is the volume of the gas in L.
n is the no. of moles of the gas in mol.
R is the general gas constant,
T is the temperature of the gas in K.
- If P and T are constant, and have different values of n and V:
<em>(V₁n₂) = (V₂n₁).</em>
V₁ = 25.5 L, n₁ = 3.5 mol.
V₂ = ??? L, n₂ = 3.5 mol - 1.9 mol = 1.6 mol.
<em>∴ V₂ = (V₁n₂)/(n₁)</em> = (25.5 L)(1.6 mol)/(3.5 mol) =<em> 11.66 L.</em>
When you are tuning an instrument it changes the sound of the instrument
