Answer:
A. Alkaline Metals
Explanation:
I majored in Chemistry
Si se encierran 100 gramos de benceno C6H6 en un recipiente con aire, se observa que, al cabo de cierto tiempo, se han evaporado 1,273 gramos, logr´andose as´ı la saturaci´on del aire con vapor de benceno. En cambio, si se disuelven 10 gramos de un soluto no vol´atil en 100 gramos de benceno y la mezcla se coloca en el recipiente anterior y a la misma temperatura, se observa que se han evaporado 1,205 gramos de benceno. A partir de estos datos, deducir la masa molecular de la sustancia disuelta.
Answer:
La masa molar de la sustancia disuelta es de aproximadamente 138,473 g/mol
Explanation:
Los parámetros dados son;
La masa de benceno en el recipiente = 100 gramos
La masa de benceno que se evapora del benceno puro = 1.273 gramos
La masa del soluto no volátil disuelto en 100 gramos de benceno = 10 gramos
La masa de benceno que se evapora de la mezcla = 1.205 gramos
Según la ley de Raoult, tenemos;
[tex]P_ {solucion} = P_ {solvente} \times X _ {solvente}[/tex]
Dónde;
[tex]P_ {solucion}[/tex] = La presión de vapor de la solución.
[tex]P_ {solvente}[/tex] = La presión de vapor del solvente
[tex]X_ {solvente}[/tex] = La fracción molar del solvente
Por lo tanto;
[tex]X_ {solvente} = \dfrac {P_ {solucion}} {P_ {solvente}}[/tex]
Según la ley de los gases ideales, tenemos;
[tex]P \times V = n \times R \times T = \dfrac{m}{M} \times R \times T[/tex]
Dónde;
P = La presión del gas
V = El volumen ocupado por el gas
m = La masa del gas
M = La masa molar del gas
R = La constante universal de los gases
T = La temperatura del gas
n = El número de moles del gas
Por lo tanto;
[tex]P = \dfrac{m \times R \times T}{M \times V}[/tex]
Donde R, T, M y V son constantes, tenemos P ∝ m
[tex]\therefore X_ {solvente} = \dfrac {P_ {solucion}} {P_ {solvente}} = \dfrac {Masa \ evaporada \ de \ solucion} {Masa \ evaporada \ de \ solvente} = \dfrac {1.205 \ g} {1.273 \ g} \approx 0.9466[/tex]
[tex]X_ {solvente}[/tex] ≈ 0.9466
[tex]X_ {solvente} = \dfrac {El \ numero \ de \ moles \ del \ solvente} {El \ total \ numero \ de \ moles \ de \ la \ solucion}[/tex]
El número de moles del solvente, C₆H₆ = (Masa de C₆H₆) / (La masa molar de C₆H₆) = 100 g / (78.11 g.mol) ≈ 1.28025 moles
El número de moles del solvente, C₆H₆ ≈ 1.28025 moles
El número total de moles = El número de moles del solvente, C₆H₆ + El número de moles del soluto no volátil, [tex]n_ {soluto}[/tex]
[tex]\therefore X_ {solvente} = 0.9466 = \dfrac {1.28025 \ moles} {1.28025 \ moles + n_ {soluto}}[/tex]
0.9466 × (1.28025 moles + [tex]n_ {soluto}[/tex]) = 1.28025 moles
1.21189 moles + 0.9466 × [tex]n_ {soluto}[/tex] = 1.28025 moles
[tex]n_ {soluto}[/tex] = (1.28025 - 1.21189)/0.9466 moles ≈ 0.07221635 moles
[tex]\therefore \dfrac {Masa \ de \ soluto} {Molar \ masa \ de \ soluto} = \dfrac {10 \ g} {Molar \ masa \ de \ soluto} \approx 0.07221635 \ moles[/tex]
[tex]\ Masa \ molar \ de \ soluto = \dfrac {10 \ g} {0.07221635 \ moles} \approx 138.473 \ g / moles[/tex]
La masa molar de la sustancia disuelta (el soluto) ≈ 138,473 g/mol
Distance and mass are factors that affect the force of
Answer:
Gravity is a fundamental underlying force in the universe. The amount of gravity that something possesses is proportional to its mass and the distance between it and another object.
Explanation:
Hope it helped, brainliest???
What is the percent composition of C3H8?
Answer: Hydrogen - 18.286%( mass present)
Carbon - 81.714%(mass present)
Explanation:
Mass percentage does not have any unit as numerator and denominator contains the same unit. Therefore, the percent composition of C and H in C[tex]_3[/tex]H[tex]_8[/tex] is 81.8% and 18% respectively.
What is percentage by mass?Mass percentage represents the the percentage of each element that is making a particular compound.
Mathematically,
Percentage of mass = (component’s mass ÷ total mass) x 100%
Atomic weight of different element of calcium phosphate
C= 12g/mol , H=1g/mol
Total mass of Carbon element in C[tex]_3[/tex]H[tex]_8[/tex] = 12 × 3 = 36
Total mass of hydrogen atom in C[tex]_3[/tex]H[tex]_8[/tex] = 1 × 8 = 8
Total molar mass of C[tex]_3[/tex]H[tex]_8[/tex] =36 + 8 =44 g/mole
Percentage of carbon in C[tex]_3[/tex]H[tex]_8[/tex] =36/44× 100 =81.8%
Percentage of hydrogen in C[tex]_3[/tex]H[tex]_8[/tex] =(8÷44)×=18%
Therefore, the percent composition of C and H in C[tex]_3[/tex]H[tex]_8[/tex] is 81.8% and 18% respectively.
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Which is a statement of the second law of thermodynamics?
O A. Entropy tends to increase in a system.
O B. Molecular motion stops at absolute zero.
O C. The net reaction rate is zero at equilibrium.
O D. Energy cannot be created or destroyed.
Answer:
A: Entropy tends to increase in a system
Which is a statement of the second law of thermodynamics?
O A. Entropy tends to increase in a system.
O B. Molecular motion stops at absolute zero.
O C. The net reaction rate is zero at equilibrium.
O D. Energy cannot be created or destroyed.
ITS A
What causes surface water to move
Answer:
C - Wind
Explanation:
its C or wind because global wind systems control the surface water
Answer:
Wind
Explanation:
surface water from oceans move from the wind I assume it is the same for all bodies of water
the average diameter of an adult human eyeball is 24mm what is the diameter in dm
Answer: 0.24 dm
Explanation:
formulas for volume
Shape Formula Variables
Cube V=s3 s is the length of the side.
Right Rectangular Prism V=LWH L is the length, W is the width and H is the height.
Prism or Cylinder V=Ah A is the area of the base, h is the height.
Which statement below is not part of the cell theory? a. All living things have many cells b All living things are made of one or more cells c cells are the basic unit of structure and function in living things d All cells come from other cells
Answer:
c
Explanation:
I know it's c because I have done the test
What does it mean when you ask your dad whats he going to do with the chikens and hes says feed them some fried chiken?
Answer:
It means your dad is making those chickens cannibal's.......
Explanation:
Answer:
Hes gonna cook those chickens.....
Which object has the greatest inertia
Answer:
D
Explanation:
lighter objects have higher inertia
What Elements that have an atomic number less than 37 and atomic mass greater than 78.4u?
Answer:
krypton
bromine
selenium
Step 2: measure the area of the top of the syringe
I am unsure if this is correct, but this might be the whole section:
The top of the syringe is a circle. You need to compute its area for use in later computations of pressure values. Start by using a ruler to measure the diameter. Estimate to the nearest 0.01 cm. Answer: 3.60 cmDivide by two to find the radius. Maintain significant figures. Answer: 1.80 cmSubstitute the radius into the formula A = πr² to find the area of the top of the syringe. Maintain significant figures. Answer: 10.2 cm²If the electronnegavity difference between elements A and X is 0.8, the bond in AX will most likely be what?
Answer:
Polar covalent bond
Explanation:
When the electronegativity difference between two elements A and X is 0.8, the bond AX formed will most likely be a polar covalent bond.
A polar covalent bond is one whose electronegativity difference is between 0.5 and 2.1.
In such a bond type, we have heteronuclear species with one of the species having a higher electronegativity value.
When electronegativity difference is less than 0.5, a non-polar covalent bond forms. If the value is greater than 2.1, an ionic bond will form.what is ionizable hydrogen and why we say it replaceable hydrogen
Answer:
only hydrogen atoms that are part of a highly polar covalent bond are ionizable. The hydrogen atom is attracted to the lone pair of electrons in a water molecule when HCl is dissolved in water. The result is that the H−Cl bond breaks, with both bonding electrons remaining with the Cl, forming a chloride ion.
Explanation:
Answer:
In an acid molecule, hydrogen atoms may be substituted by metal atoms.
Explanation:
It is ionizable only to hydrogen atoms that are part of a strongly polar covalent bond. As HCl is dissolved in water, the hydrogen atom is drawn to the lone pair of electrons in a water molecule. The effect is that the H-Cl bond splits, with the Cl remaining with both bonding electrons, forming a chloride ion.
6. Would you describe each of these temperatures as warm, hot, or cold?
b. 60 °C
a. 100 K
c. 250 K
d. 25 °C
e.
300 K
f. -100 °C
g. 400 K
Answer:
b: Hot
a: Cold
c: Cold
d: Warm
e: Warm
f: Cold
g: Hot
Explanation:
:)
ALL I ask is you answer correctly I'm having a bad day ! :(
Jimmy Fallon was playing with acids and bases and was trying to determine how many grams of Copper (I) Hydroxide he would need to create 48.76 grams of Copper (I) Phosphate when reacting it with Phosphoric Acid.
Answer:
i have no clue whats going on here but imma act like i do.....
Explanation:
What is not a mass of 1 mole of a substance?
Explanation:
been defined in such a way. It is defined as the numbers of particles in 12 g of 12C. If it were 24 g instead of 12 g, then the weight of 1 mole of substance would equal 2 times the atomic/molecular mass in grams.
what is the pOH of a solution if the concentration of hydronium ionsis 8.9x10-9
pOH of a solution = 5.95
Further explanationGiven
The concentration of hydronium ions : 8.9 x 10⁻⁹
Required
pOH
Solution
pOH = - log[OH]
[H₃O⁺]= 8.9 x 10⁻⁹
pH = - log[H₃O⁺]
pH = 9 - log 8.9
pH = 8.05
pH + pOH = 14
pOH = 14-pH
pOH= 14-8.05
pOH = 5.95
Which nuclear equation represents a spontaneous decay?
(1) Rn 21% Po + He
(2) 13 Al + He 18P + on
(3) 235 U + in ~ 13% Ba + Kr + 3n
(4) Li + H → He + He
a. 1
b. 2
C 3
d. 4
Answer:
a. 1
Explanation:
Radon is a member of group 18. It is an odorless heavy gas, that emanates from materials that contain uranium.
Rn is a decay product of 226-Ra, a member of the uranium decay series. The spontaneous decay of Rn decay leads to the emission of an alpha particle.
Rn has a half-life of about 3.8 days and its decay product is 218Po.
The nuclear reaction which shows a spontaneous decay is Rn 21% Po + He.
What is spontaneous reaction?
Those reaction in which value of their enthalpy change and change in Gibb's free energy is negative, are spontaneous in nature.
Among all of the given reaction, only first reaction is spontaneous in nature because the given element Radon (Rn) is the product of the decay of uranium series. And in this reaction energy is emitted in the form of alpha particles.
Hence, option (1) is correct.
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The molar mass of NaCl is 58.44 g/mol. What is the molarity of a solution that
contains 120 g of NaCl in 0.750 L of solution?
0.649 M
3.00 M
2.74 M
2.05 M
How many different elements are involved in the chemical reaction shown
Ca+2H2O>ca(OH)2+H2
Explanation:
1.ca
2.H
3.O
.................
does anyone have the 2020 paper for chemistry
Answer:
Erm.......... can you clarify what "paper", you just said "paper" there's a lot.
Explanation:
what physical properties can be used to separate heterogeneous mixture's?
Over time, repeated cycles of heating and cooling can cause a rock to crack. The rock may then break into smaller pieces. What is this process called?
Finn is investigating how energy affects objects. He adds energy to an object as shown.
Will the energy he has added cause the object to move?
no, because the light energy from the battery will change its mass
no, because heat energy from the battery will change its temperature
yes, because the battery’s mechanical energy will make the motor run
yes, because the battery’s electrical energy will make its wheels turn
Answer:
Yes because
Explanation:
Answer:yes because the battery's electrical energy will make the wheels turn.
Which statement is true regarding a catalyst?
A). A catalyst increases the activation energy for a chemical reaction.
b). A catalyst decreases the difference in energy for a chemical reaction.
c). A catalyst allows the reactants to start at a higher energy level.
d). A catalyst lowers the activation energy for a chemical reaction.
Answer:
d). A catalyst lowers the activation energy for a chemical reaction.
Explanation:
From the given choices, it is true that a catalyst lowers the activation energy for a chemical reaction.
The activation energy is the energy barrier that must be overcome before a chemical reaction can occur.
Some reactions have very high activation energy and would not occur without the introduction of a catalyst.
The catalyst brings the reactants into contact by removing the energy deficiency in the system.
A marble rolls off horizontally from the edge of table top 1.50 m above the floor. it strikes the floor 2.0 m from the base of the table. (a) how long does it take the marble to reach the floor? (b) What is its initial speed?
please help me masters(;´༎ຶٹ༎ຶ`)
a. t=0.553 s
b. vox(horizontal speed) = 3.62 m/s
Further explanationGiven
h = 1.5 m
x = 2 m
Required
a. time
b. vo=initial speed
Solution
Free fall motion
a. h = 1/2 gt²(vertical motion=h=voyt+1/2gt²⇒voy = 0)
[tex]\tt t=\sqrt{\dfrac{2h}{g} }[/tex]
t = √2h/g
t = √2.1.5/9.8
t=0.553 s
b. x=vox.t(horizontal motion)
[tex]\tt x=v_{ox}\times t[/tex]
vox=x/t
vox=2/0.553
vox=3.62 m/s
calculate the mass of a sample of cobalt containing 3.31x10^22 atoms
Answer:
Mass = 3.24 g
Explanation:
Given data:
Number of atoms of cobalt = 3.31 × 10²² atoms
Mass of cobalt atoms = ?
Solution:
We will calculate the number of moles of cobalt by using Avogadro number.
1 mole contain 6.022× 10²³ atoms
3.31 × 10²² atoms × 1 mol / 6.022× 10²³ atoms
0.549 mol × 10⁻¹
0.0549 mol
Mass of cobalt:
Mass = number of moles × molar mass
Mass = 0.0549 mol × 58.93 g/mol
Mass = 3.24 g
Which of the following elements is the least electronegative?
A. NA
B. Al
C. Cl
D. Si
Answer:
na
Explanation:
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Cl (chlorine) ion is negatively charged.
When air is cooled, its density...
A. Increases
B. Decreases
C. Remains the same
Answer + Explanation:
When air is cooled, its density increases.
A. increases
Answer:
The answer to your question is A.
Explanation:
when air is cooled, it's density Increases