The correct answer is D. Frequency. I just took the test.
Answer:
N₂H₆
Explanation:
A 1.000 g sample of nitrogen combined with a 0.0720 g sample of hydrogen to form N₂H₂ .
1.000 g of nitrogen combines with 0.2160 g of hydrogen in the next compound .
In this compound the component of nitrogen remains the same but the component of hydrogen becomes .2160 / .0720 = 3 times .
Hence component of hydrogen in the new compound will change from
H2 to H6 .
Hence the chemical formula of new compound will be
N₂H₆ .
Answer:
Percentage yield = 30%
Explanation:
Given data:
Number of moles of NO = 7.0 mol
Number of moles of O₂ = 5 mol
Number of moles of NO₂ = 3 mol
Percentage yield = ?
Solution:
Chemical equation:
2NO + O₂ → 2NO₂
Now we will compare the moles of NO₂ with NO and O₂ .
NO : NO₂
2 : 2
7.0 : 7.0
O₂ : NO₂
1 : 2
5.0 : 2 ×5.0 = 10 mol
The number of moles of NO₂ produced by NO are less it will be limiting reactant.
Mass of NO₂ = moles × molar mass
Mass of NO₂ = 10 mol × 46g/mol
Mass of NO₂ = 460 g
Actual yield of NO₂:
Mass of NO₂ = moles × molar mass
Mass of NO₂ = 3 mol × 46g/mol
Mass of NO₂ = 138 g
Percentage yield:
Percentage yield = Actual yield/theoretical yield × 100
Percentage yield = 138 g/ 460 g × 100
Percentage yield = 30%
