All categories

3 years ago

How many moles of gas are present when you collect 35.83 mL of the gas over water at 25.3°C and 0.97 atm?

Chemistry

2 answers:

Harlamova29_29 [7]3 years ago

7 0

Answer is: 0.00142 moles of gas are present.

Ideal gas law: p·V = n·R·T.

p = 0.97 atm.; pressure of the gas.

T = 25.3 + 273.15.

T = 298.45 K; temperature of the gas.

V = 35.83 mL ÷ 1000mL/L.

V = 0.03583 L; volume of the gas.

R = 0.08206 L·atm/mol·K; gas constant.

n = 0.97 atm · 0.03583 L ÷ (0.08206 L·atm/mol·K · 298.45 K).

n = 0.00142 mol; amount of the gas.

Oksana_A [137]3 years ago

3 0

Use Ideal Gas equation since values are given in Pressure (P), Volume (V), Temperature (T).
P V = n R T ; n= PV / RT
You can't use 1 mole= 22.4 L equation. Temperature and pressure values are not standard. ( 1 atm, 0

To choose the value of R ( gas constant), check out the units of other values in the equation. They are in atm,liter, kelvin, and mole. So, its value is 0.082 L atm/ K mol.

P= 0.97 atm
V= 35.83 * 10 ⁻³ L (conversion from ml to, just multiplied by 10 ⁻³ )
R= 0.082 L atm/ K mol
T= (25.3 + 273) K ( recall Kelvin = Celcius + 273; K= °C + 273<span>)
</span>
Substitute values into equation of n= PV / RT

n= (0.97 atm) (35.83 * 10 ⁻³ L) / (0.082 L atm/ K mol) (298.3 K)= 0.014 mole

The answer is 0.014 mole

You might be interested in

(a) What is the basis of the approximation that avoids using the quadratic formula to find an equilibrium concentration?

rusak2 [61]

The approximation is valid because is very small.

Calculation of concentration:

Since

0.85 M 0 0

(0.85-x)M x x

Now the value of x should be

x = 0.0000229

So based on this, the above concentration should be determined.

Now you will solve using the quadratic formula instead of iterations, to show that the same value of x is obtained either way. using the quadratic equation to calculate [h3o+] in 0.00250 m hno2, what are the values of a, b, c and x , where a, b, and c are the coefficients in the quadratic equation ax2+bx+c=0, and x is [h3o+]? recall that ka=4.5×10−4 .

a: 1

b: 4.5x10⁻⁴

c: 1.125x10⁻⁶

[H₃O⁺] = 0.000859M

As HNO₂ is a weak acid, its equilibrium in water is:

HNO₂(aq) + H₂O(l) ⇄ H₃O⁺(aq) + NO₂⁻(aq)

Equilibrium constant, ka, is defined as:

ka = 4.5x10⁻⁴ = [H₃O⁺] [NO₂⁻] / [HNO₂] (1)

Equilibrium concentration of each specie are:

[HNO₂] = 0.00250M - x

[H₃O⁺] = x

[NO₂⁻] = x

Replacing in (1):

4.5x10⁻⁴ = x × x / 0.00250M - x

1.125x10⁻⁶ - 4.5x10⁻⁴x = x²

0 = x² + 4.5x10⁻⁴x - 1.125x10⁻⁶

As the quadratic equation is ax² + bx + c = 0

Coefficients are:

a: 1

b: 4.5x10⁻⁴

c: 1.125x10⁻⁶

Now, solving quadratic equation:

x = -0.0013 → False answer, there is no negative concentrations.

x = 0.000859

As [H₃O⁺] = x; [H₃O⁺] = 0.000859M

To know more about Equilibrium constant

brainly.com/question/19340344

#SPJ4

7 0

2 years ago

Which is warmer -30C or -30 F?

Burka [1]

-30°C is more warmer than -30°F...!

Always Celsius is warmer than farheniet and also in coldness Celsius is colder than farheneit.

8 0

2 years ago

Read 2 more answers

Calculate the cell potential at 25oC under the following nonstandard conditions: 2MnO4-(aq) + 3Cu(s) + 8H+(aq) ⟶ 2MnO2(s) + 3Cu2

baherus [9]

Answer:

1.346 v

Explanation:

1) Fist of all we need to calculate the standard cell potential, one should look up the reduction potentials for the species envolved:

(oxidation) $Cu_{(s)}$ → $Cu^{2+}_{(aq)} +2e$ E°=0.337 v

(reduction) $MnO_{4 (aq)} + 3e + 4H^{+}_{(aq)}$ → $MnO_{2 (aq)}+2H_{2}O$ E°=1.679 v

(overall) $2MnO_{4 (aq)}+3Cu_{(s)}$ +8H^{+}_{(aq)}→ $3Cu^{2+}_{(aq)}+2MnO_{2 (aq)}+4H_{2}O$ E°=1.342 v

2) Nernst Equation

Knowing the standard potential, one calculates the nonstandard potential using the Nernst Equation:

$E=E^{0} -\frac{RT}{nF}Ln\frac{[red]}{[ox]}$

Where 'R' is the molar gas constant, 'T' is the kelvin temperature, 'n' is the number of electrons involved in the reaction and 'F' is the faraday constant.

The problem gives the [red]=0.66M and [ox]=1.69M, just apply to the Nernst Equation to give

$E=1.342 -\frac{298.15*8.314}{6*96500}Ln\frac{[.66]}{[1.69]}=1.346$

E=1.346

5 0

3 years ago

Water has a density of 1.0 g/ml. which of these objects will float in water? object i: mass = 50.0 g; volume = 40.2 ml object ii

Oksana_A [137]

<span>Object I would be it</span>

8 0

3 years ago

A chemist mixes sodium with water and witnesses a violent reaction between the metal and water. this is best classified as

Tema [17]

A law is statement about an observed concept. A theory involves the explanation of scientific concepts or principles. A hypothesis is the predicted explanation about some concepts that has to be tested in order to prove it to be right. An observation is the observing the results of a scientific experiment carried out to test an hypothesis.

Here the given statement 'A chemist mixes sodium with water and witnesses a violent reaction between the metal and water,' can be classified as an observation as it explains what the chemists observes as a result of his chemical experiment or test..

8 0

3 years ago