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2 years ago

Pis

Chemistry

1 answer:

loris [4]2 years ago

8 0

Answer:

5.00×10-19 J

Explanation:

E = hv

but v = c ÷ wavelength

E = (6.626×10-34) × ((3×10^8)÷(398×10-9))

= 4.9945×10-19

≈5.00×10-19

Hope this helps

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A solution contains two isomers, n-propyl alcohol and isopropyl alcohol, at 25°C. The total vapor pressure is 38.6 torr. What ar

Leona [35]

Answer:

Mole fraction of alcohols in liquid phase $x_1=0.2727\& x_2=0.7273$ .

Mole fraction of alcohols in vapor phase $y_1=0.1468\& y_2=0.8516$ .

Explanation:

The total vapor pressure of the solution = p =38.6 Torr

Partial vapor pressure of the n-propyl alcohol = $p^{o}_1=21.0 Torr$

Partial vapor pressure of the isopropyl alcohol = $p^{o}_2=45.2 Torr$

$p=x_1\times p^{o}_1+x_2\times p^{o}_2$ (Raoult's Law)

$p=x_1\times p^{o}_1+(1-x_1)\times p^{o}_2$

$38.6 Torr=x_1\times 21.0 Torr+(1-x_1)\times 45.2 Torr$

$x_1=0.2727$

$x_2=1-0.2727=0.7273$

$x_1\& x_2$ is mole fraction in liquid phase.

Mole fraction of components in vapor phase $y_1\& y_2$

$p_1=y_1\times p$ (Dalton's law of partial pressure)

$y_1=\frac{p_1}{38.6 Torr}=\frac{p^{o}_1\times x_1}{38.6 Torr}$

$y_1=\frac{21.0 Torr\times 0.2727}{38.6 Torr}=0.1468$

$y_1=\frac{p_2}{38.6 Torr}=\frac{p^{o}_2\times x_2}{38.6 Torr}$

$y_2=\frac{45.2 Torr\times 0.7273}{38.6 Torr}=0.8516$

Mole fraction of alcohols in vapor phase $y_1=0.1468\& y_2=0.8516$

5 0

3 years ago

13. An aerosol spray can of deodorant with a volume of 0.410 L contains 3.0 g of propane gas (CH3) as propellant. What is the pr

qaws [65]

Answer: The pressure in the can is 4.0 atm

Explanation:

According to ideal gas equation:

$PV=nRT$

P = pressure of gas = ?

V = Volume of gas = 0.410 L

n = number of moles = $\frac{\text {given mass}}{\text {Molar mass}}=\frac{3.0g}{44.1g/mol}=0.068mol$

R = gas constant = $0.0821Latm/Kmol$

T =temperature = $20^0C=(20+273)K=293K$

$P=\frac{nRT}{V}$

$P=\frac0.068mol\times 0.0820 L atm/K mol\times 293K}{0.410L}=4.0atm$

Thus the pressure in the can is 4.0 atm

8 0

3 years ago

consider this reaction at equilibrium at a total pressure: 2h2o(g) o2(g) 2h2o2(g) suppose the volume of this system is twice its

Daniel [21]

The total pressure when the new equilibrium is stabilized is half of the initial pressure of the system.

The given chemical reaction at a stable equilibrium is,

2H₂O(g)+O₂(g) = 2H₂O₂(g)

According to the ideal gas equation,

PV = nRT

P is pressure,

V is volume,

n is moles

R is gas constant,

T is temperature.

Assuming the temperature is constant.

If the volume of the system is twice the initial volume then the total pressure at the new equilibrium can be found out as,

P₁V₁ = P₂V₂

Where, P₁ and V₁ are initial volume and pressure while P₂ and V₂ are final pressure and volume.

If V₂ = 2V₁,

P₂ = P₁/2

So, the final total pressure will be half of the initial pressure.

To know more about equilibrium, visit,

brainly.com/question/517289

#SPJ4

5 0

1 year ago

If the weight of displaced liquid and the weight of an object are the same, the object will:

s344n2d4d5 [400]

Answer:

Float

Explanation:

If the weight of liquid displaced and the weight of an object are the same, the object will float in the liquid.

From Archimedes principle, when an object is immersed in fluid, a force called upthrust supports it and it equal to the weight of the liquid displaced.

When in a liquid, the weight of the liquid displaced is the same as that of the of the object, it will float and not sink.

7 0

3 years ago

explain how energy changes from one form to another in a exothermic reaction. in an endothermic reaction.

Alexxx [7]

Answer:

Exothermic reaction: In exothermic reaction, energy is transferred to the surroundings, and the surrounding temperature increases, this is known as exothermic reaction. In other words energy exits in exothermic reaction. Some example of exothermic reactions are:

1) Neutralisation reaction.

2) Combustion reaction.

3) Some oxidation reaction.

Endothermic reaction: In endothermic reaction, energy is taken in from the surrounding, and the surrounding temperature decreases, this is known as endothermic reaction. In other words energy enters in endothermic reaction. Some example of exothermic reactions are:

1) Thermal decomposition.

2) Reaction between citric acid and sodium hydrogen carbonate.

6 0

3 years ago