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2 years ago

7. How many moles of argon are there in 20.0 L, at 25 degrees Celsius and 96.8 kPa?

Chemistry

2 answers:

suter [353]2 years ago

4 0

<h3>Answer:</h3>

0.8133 mol

<h3>Solution:</h3>

Data Given:

Moles = n = ??

Temperature = T = 25 °C + 273.15 = 298.15 K

Pressure = P = 96.8 kPa = 0.955 atm

Volume = V = 20.0 L

Formula Used:

Let's assume that the Argon gas is acting as an Ideal gas, then according to Ideal Gas Equation,

P V = n R T

where; R = Universal Gas Constant = 0.082057 atm.L.mol⁻¹.K⁻¹

Solving Equation for n,

n = P V / R T

Putting Values,

n = (0.955 atm × 20.0 L) ÷ (0.082057 atm.L.mol⁻¹.K⁻¹ × 298.15 K)

n = 0.8133 mol

Serhud [2]2 years ago

3 0

The moles of argon that are there in 20.0 L , at 25 c and 96.8 KPa is = 0.7814 moles

<em><u>calculation</u></em>

by use of the ideal gas equation

that is PV=nRT where;

P(pressure)= 96.8 kpa

V(volume)= 20.0 L

n (moles) = ?

R( gas constant)= 8.314 kpa/k/mol

T( temperature)= 25 +273= 298 K

make n the formula of the subject

n = PV/RT

n is therefore= [ (96.8 KPa x 20.0 l) /( 8.314 kpa/k/mol x 298 k)]

answer =0.781 moles

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2 years ago

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xenn [34]

The given question is incomplete. The complete question is :

For the reaction $PCl_5(g)\rightleftharpoons PCl_3(g)+Cl_2(g)$ at equilibrium, which statement correctly describes the effects of increasing pressure and adding $PCl_5$ , respectively

a) Increasing pressure causes shift to reactants, adding $PCl_5$ causes shift to products.

b) Increasing pressure causes shift to products ,adding $PCl_5$ causes shift to reactants.

c) Increasing pressure causes shift to products, adding $PCl_5$ causes shift to products.

d) Increasing pressure causes shift to reactants,adding $PCl_5$ causes shift to reactants

Answer: Increasing pressure causes shift to reactants, adding $PCl_5$ causes shift to products.

Explanation:

Any change in the equilibrium is studied on the basis of Le-Chatelier's principle.

This principle states that if there is any change in the variables of the reaction, the equilibrium will shift in the direction to minimize the effect.

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$PCl_5(g)\rightleftharpoons PCl_3(g)+Cl_2(g)$

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2 years ago

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Marina CMI [18]

Answer:

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Answer:

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2 years ago

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