All categories

3 years ago

What mass of KNO3 would be needed to produce 18.4 liters of oxygen gas, measured at 1.50 x 10^3 kPa and 15 degrees Celsius?

Chemistry

1 answer:

Brut [27]3 years ago

7 0

Answer:-

2328.454 grams

Explanation:-

Volume V = 18.4 litres

Temperature T = 15 C + 273 = 288 K

Pressure P = 1.5 x 10^ 3 KPa

We know universal Gas constant R = 8.314 L KPa K-1 mol-1

Using the relation PV = nRT

Number of moles of oxygen gas n = PV / RT

Plugging in the values

n = (1.5 x 10^3 KPa ) x ( 18.4 litres ) / ( 8.314 L KPa K-1 mol-1 x 288 K)

n = 11.527 mol

Now the balanced chemical equation for this reaction is

2KNO3 --> 2KNO2 + O2

From the equation we can see that

1 mol of O2 is produced from 2 mol of KNO3.

∴ 11.527 mol of O2 is produced from 2 x 11.527 mol of KNO3.

= 23.054 mol of KNO3

Molar mass of KNO3 = 39 x 1 + 14 x 1 + 16 x 3 = 101 grams / mol

Mass of KNO3 = 23.054 mol x 101 gram / mol

= 2328.454 grams

You might be interested in

1. A substance, A₂B, has the composition by mass of 60% A and 40% B. What is the composition of AB₂ by mass?

Lubov Fominskaja [6]

This may help you
Use an arbitrary mass, 100 g is an easy number to work with. 60% of 100 g is 60 g, there are two A's. Each A is 30 g 40 g is B, and there is only one, so B is 40 g. AB2, would have a mass of 30 g + 2*40 g = 110 g The new percent by mass composition of A is: 30g110g∗100%=27.3% The new percent by mass composition of B is: 80g110g∗100%=72.7%

8 0

3 years ago

Describe the motion of a pendulum in terms of kinetic and potential energy. As the pendulum moves from its greatest to lowest he

Bezzdna [24]

Highest height : Potential energy = high | Kinetic energy = low

Lower height: kinetic Potential energy = low | Kinetic energy = high

*Remember it by when its higher thats when it has "high potential" :)*

6 0

3 years ago

Why do we experience the changing of the seasons on earth

iren2701 [21]

Answer:

Earth's axis and position around the sun.

Explanation:

Earth's tilted axis causes the seasons to change. Throughout the year, different parts of Earth acquire the Sun's most direct rays(Or heat) because of the orbital rotation of Earth. So, when the North Pole tilts toward the Sun, it's summer inside the Northern Hemisphere. And whilst the South Pole tilts towards the Sun, it is winter within the Northern Hemisphere and vise versa.

4 0

3 years ago

We can see water change state, from ice to steam. This is a __________ change in matter. A) chemical B) combustion Eliminate C)

Gemiola [76]

Answer: Option (C) is the correct answer.

Explanation:

When chemical composition of a substance is not changing in a chemical reaction then it is known as a physical change.

For example, when water change state, from ice to steam then it means solid state is changing into gaseous state.

Therefore, it is a physical change.

And, a reaction which causes change in chemical composition is known as a chemical change.

For example, $Li + Cl \rightarrow LiCl$

Thus, we can conclude that we can see water change state, from ice to steam. This is a physical change in matter.

4 0

3 years ago

How many electrons in an atom can have the following quantum

gavmur [86]

The answer for the following question is explained.

Therefore the number of electrons present with the values n = 5, l = 2, m = -2, s = +1/2 is one(1).

Explanation:

Here;

n represents the principal quantum number

l represents the Azimuthal quantum number

m represents magnetic quantum number

s represents spin quantum number

n = 5,

l = 2,

m = -2,

s = +1/2

Here, it implies 5d orbital.

In the 5d orbital, 10 electrons.

As the magnetic quantum number is -2, and so it can have 1 electron.

Therefore the number of electrons present with the values n = 5, l = 2, m = -2, s = +1/2 is one(1)

7 0

3 years ago