calculate the mass and number of molecules and number of each constituent atoms in 3.4 gram of ammonia gas
Answers
Answer:
The molar mass of the ammonia gas is 17 g mol¯¹.
The number of molecules in 3.4 gram of ammonia is 1.2044 × 10²³.
The number of nitrogen atoms in 3.4 gram of ammonia is 1.2044 × 10²³.
The number of hydrogen atoms in 3.4 gram of ammonia is 3.6132 × 10²³.
Explanation:
We have given that the mass of the ammonia gas is 3.4 gram.
We have to calculate the mass of ammonia gas, number of molecules of ammonia gas and number of atoms of each of the constituents.
We know that,
Molecular formula of ammonia gas = NH₃
∴ Molar mass of ammonia = [ ( 1 × Atomic mass of nitrogen ) + ( 3 × Atomic mass of hydrogen ) ]
⇒ Molar mass of ammonia = [ ( 1 × 14 ) + ( 3 × 1 ) ]
⇒ Molar mass of ammonia = ( 14 + 3 )
⇒ Molar mass of ammonia = 17 g mol¯¹
∴ The molar mass of the ammonia gas is 17 g mol¯¹.
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Now,
Number of moles of ammonia = ( Mass of ammonia ) / ( Molar mass of ammonia )
⇒ Number of moles of ammonia = 3.4 g / 17 g mol¯¹
⇒ Number of moles of ammonia = 3.4 ÷ 17 mol
⇒ Number of moles of ammonia = 0.2 mol
Now, we know that,
Number of molecules of ammonia = Number of moles × Avogadro's number
⇒ Number of molecules of ammonia = n × Nᴀ
⇒ Number of molecules of ammonia = 0.2 × 6.022 × 10²³
⇒ Number of molecules of ammonia = 1.2044 × 10²³
∴ The number of molecules in 3.4 gram of ammonia is 1.2044 × 10²³.
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Now,
Number of nitrogen atoms = Number of nitrogen atoms in ammonia × Number of molecules of ammonia
⇒ Number of nitrogen atoms = 1 × 1.2044 × 10²³
⇒ Number of nitrogen atoms = 1.2044 × 10²³
∴ The number of nitrogen atoms in 3.4 gram of ammonia is 1.2044 × 10²³.
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Now,
Number of hydrogen atoms = Number of hydrogen atoms in ammonia × Number of molecules of ammonia
⇒ Number of hydrogen atoms = 3 × 1.2044 × 10²³
⇒ Number of hydrogen atoms = 3.6132 × 10²³
∴ The number of hydrogen atoms in 3.4 gram of ammonia is 3.6132 × 10²³.