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levacccp [35]
2 years ago
11

What does the mass number of an atom represent?.

Chemistry
1 answer:
mamaluj [8]2 years ago
8 0

Answer:

the sum of the numbers of protons and neutrons present in the nucleus of an atom.

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Hydrogen gas (a potential future fuel) can be formed by the reaction of methane with water according to the following equation:
rusak2 [61]

Answer:

60.42% is the percent yield of the reaction.

Explanation:

Moles of methane gas at 734 Torr and a temperature of 25 °C.

Volume of methane gas = V = 26.0 L

Pressure of the methane gas = P = 734 Torr = 0.9542 atm

Temperature of the methane gas = T = 25 °C = 298.15 K

Moles of methane gas = n

PV=nRT

n=\frac{PV}{RT}=\frac{0.9542 atm\times 26.0L}{0.0821 atm L/mol K\times 298.15 K}=1.0135 mol

Moles of water vapors at 700 Torr and a temperature of 125 °C.

Volume of water vapor = V' = 23.0 L

Pressure of water vapor = P' = 700 Torr = 0.9100 atm

Temperature of  water vapor = T' = 125 °C = 398.15 K

Moles of water vapor gas = n'

P'V'=n'RT'

n'=\frac{PV}{RT}=\frac{0.9100 atm\times 23.0L}{0.0821 atm L/mol K\times 398.15 K}=0.6402 mol

CH_4(g)+H_2O(g)\rightarrow CO(g)+3H_2(g)

According to reaction , 1 mol of methane reacts with 1 mol of water vapor. As we can see that moles of water vapors are in lessor amount which means it is a limiting reagent and formation of hydrogen gas will depend upon moles of water vapors.

According to reaction 1 mol of water vapor gives 3 moles of hydrogen gas.

Then 0.6402 moles of water vapor will give:

\frac{3}{1}\times 0.6402 mol=1.9208 mol of hydrogen gas

Moles of hydrogen gas obtained theoretically = 1.9208 mol

The reaction produces 26.0 L of hydrogen gas measured at STP.

At STP, 1 mole of gas occupies 22.4 L of volume.

Then 26 L of volume of gas will be occupied by:

\frac{1}{22.4 L}\times 26 L= 1.1607 mol

Moles of hydrogen gas obtained experimentally = 1.1607 mol

Percentage yield of hydrogen gas of the reaction:

\frac{Experimental}{Theoretical}\times 100

\%=\frac{ 1.1607 mol}{1.9208 mol}\times 100=60.42\%

60.42% is the percent yield of the reaction.

8 0
3 years ago
If you initially have a volume of 4 L and a temperature of 300K. Then you decreased the volume to 2 L, what is the new temperatu
ASHA 777 [7]

Answer:

T₂ = 150 K

Explanation:

Given data:

Initial volume = 4 L

Initial temperature = 300 K

Final volume = 2 L

Final temperature = ?

Solution:

The given problem will be solve through the Charles Law.

According to this law, The volume of given amount of a gas is directly proportional to its temperature at constant number of moles and pressure.

Mathematical expression:

V₁/T₁ = V₂/T₂

V₁ = Initial volume

T₁ = Initial temperature

V₂ = Final volume  

T₂ = Final temperature

Now we will put the values in formula.

V₁/T₁ = V₂/T₂

T₂ = T₁V₂/V₁  

T₂ = 300 K × 2L / 4 L

T₂ = 600 L.K / 4 L

T₂ = 150 K

3 0
3 years ago
How many cm is 0.375 ft.​
ivann1987 [24]

Answer:

11.43 cm

Explanation:

8 0
3 years ago
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How many atoms of each element are present in the compound
Lera25 [3.4K]
...............................................c
8 0
3 years ago
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HELP ASAP, TIMED ASSINGMENT
Oksanka [162]

Answer:

All of the physical and biological factors in it's environment, I think this is the answer, but I might be wrong.

Explanation:

I learned it in my school's Science class

8 0
3 years ago
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