1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Brilliant_brown [7]
3 years ago
11

typical room is 4.0 m long, 5.0 m wide, and 2.5 m high. What is the total mass of the oxygen in the room assuming that the gas i

n the room is at STP and that air contains 21% oxygen and 79% nitrogen?
Chemistry
1 answer:
andrey2020 [161]3 years ago
8 0

Answer:

mass of oxygen gas in Kg = 15.0Kg

Explanation:

Volume of air in the room = 4.0m*5.0m*2.5m = 50m³

volume of oxygen in the room = 21/100 *  50m³ = 10.5m³

using the ideal gas equation; PV=nRT

number of moles of oxygen gas, n = PV/RT

At STP, P = 1atm, V = 10.5m³ = (10.5*1000)dm³ = 10500dm³, R = 0.082 atmdm³K⁻¹mol⁻¹, T = 273K

n = 1 * 10500/ (273 *0.082)

n = 469.04 moles

mass of oxygen gas in Kg = (no of moles * molar mass)/1000

molar mass of oxygen gas = 32g

mass of oxygen gas in Kg = (469.04 * 32)/1000

mass of oxygen gas in Kg = 15.0Kg

You might be interested in
A. In the complete reaction of 22.99 g of sodium
fenix001 [56]

Answer : 58.44 g

<h3>Further explanation</h3>

The reaction

\tt Na+Cl\Rightarrow NaCl

mole ratio :

Na : Cl : NaCl = 1 : 1 : 1

Molar mass of Na : 22,989769 g/mol = 22.99 g/mol

Molar mass of Cl : 35,453 g/mol= 35.45 g/mol

Molar mass of NaCl : 58,44 g/mol

Let's check the mol for reactant (Na and Cl) and product(NaCl)

  • mol of Na :

\tt mol=\dfrac{22.99}{22.99}=1

  • mol of Cl :

\tt mol=\dfrac{35.45}{35.45}=1

Then the reactants are completed reacting because it matches the mole ratio, which is 1: 1

so that the mole of the product can be determined from the mol Na or Cl, which is 1

  • mass of NaCl :

\tt =\dfrac{mol~NaCl}{mol~Na}\times MW~NaCl\\\\=\dfrac{1}{1}\times 58.44\\\\=\boxed{\bold{58.44~g}}

3 0
4 years ago
What caused light to appear bent when it refracts ?
xz_007 [3.2K]

Answer:

Light refracts whenever it travels at an angle into a substance with a different refractive index (optical density). This change of direction is caused by a change in speed. ... When light enters a more dense substance (higher refractive index), it 'bends' more towards the normal line.

5 0
3 years ago
Read 2 more answers
you run 1 3/4 miles each day. your friend runs 4 times as far as you. how far does your friend runs each day
djverab [1.8K]
1 3/4 * 4 = 7

Your friend runs 7 miles each day.
8 0
3 years ago
an empty relative density bottle weights 20g. the bottle weights 40g when filled with petrol and 60g when filled with water. det
Kobotan [32]

Answer:

500 Kg/m³

Explanation:

From the question given above, the following data were obtained:

Mass of empty bottle = 20 g

Mass of bottle + petrol = 40 g

Mass of bottle + water = 60 g

Density of water = 1000 Kg/m³

Density of petrol =?

Next, we shall determine the mass of water. This can be obtained as follow:

Mass of empty bottle = 20 g

Mass of bottle + water = 60 g

Mass of water =?

Mass of water = (Mass of bottle + water) – (Mass of empty bottle)

Mass of water = 60 – 20

Mass of water = 40 g

Converting 40 g to Kg, we have:

1000 g = 1 Kg

Therefore,

40 g = 40 × 1 Kg / 1000 g

40 g = 0.04 Kg

Next, we shall determine the volume of the bottle by calculating the volume of water. This can be obtained as follow:

Mass of water = 0.04 Kg

Density of water = 1000 Kg/m³

Volume of water =?

Density = mass / volume

1000 = 0.04 / volume

Cross multiply

1000 × volume = 0.04

Divide both side by 1000

Volume of water = 0.04 / 1000

Volume of water = 4×10¯⁵ m³

Thus, the volume of the bottle is 4×10¯⁵ m³

Next, we shall determine the mass of the petrol. This can be obtained as follow:

Mass of empty bottle = 20 g

Mass of bottle + petrol = 40 g

Mass of petrol =?

Mass of petrol = (Mass of bottle + petrol ) – (Mass of empty bottle)

Mass of petrol = 40 – 20

Mass of petrol = 20 g

Converting 20 g to Kg, we have:

1000 g = 1 Kg

Therefore,

20 g = 20 × 1 Kg / 1000 g

20 g = 0.02 Kg

Finally, we shall determine the density of the petrol. This can be obtained as follow:

Mass of petrol = 0.02 Kg

Volume of petrol = 4×10¯⁵ m³

Density of petrol =?

Density = mass / volume

Density of petrol = 0.02 / 4×10¯⁵

Density of petrol = 500 Kg/m³

4 0
3 years ago
In ____________, electrons are gained by atoms and lost by others
Nat2105 [25]
In ions atoms lose and gain electrons
3 0
3 years ago
Read 2 more answers
Other questions:
  • Determine the number of bonding electrons and the number of nonbonding electrons in the structure of OF2. Enter the number of bo
    13·2 answers
  • The specific gravity of H2SO4 is 1.84, its density would be?
    13·1 answer
  • assuming gasoline can be represented as C8H18, how much oxygen is needed to completely burn this fuel. answer in grams of oxygen
    13·1 answer
  • 140 grams of NaNO3 was dissolved in 100 grams of water at 80 degrees Celsius. The solution is_______________.
    5·2 answers
  • Brass alloy is best described as _______.
    7·1 answer
  • Is the following nuclear equation balanced?<br>214Pb &gt; He + 240 Hg<br>yes<br>no​
    13·1 answer
  • If a gas occupies 2.3 liters at a pressure of 1.9 atm, what will be its volume at a pressure of 3.8 atm?
    5·2 answers
  • HELP PLEASE ASAP!!!!!
    6·2 answers
  • Briefly describe how you can use spectra as evidence of nuclear fusion in stars.
    8·1 answer
  • How many moles is 25g of ammonia (NH3)?
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!