Respuesta :
Answer:
CH2
Explanation:
When a hydrocarbon is burnt in air or oxygen, there are two products only, these are water and carbon iv oxide.
Fuel + Oxygen—-> Water + Carbon iv oxide
We can get the formula through calculations as follows.
From the mass of carbon iv oxide produced, we can get the number of moles of carbon produced. We first divide the mass by the molar mass of carbon iv oxide. The molar mass of carbon iv oxide is 44g/mol
The number of moles of carbon iv oxide is 0.44/44 = 0.01
Since there is only one carbon atom in CO2, the number of moles of carbon is same as above I.e 0.01 moles
From the number of moles of water, we can get the number of moles of hydrogen. To get the number of moles of water, we need to divide the mass of water by its molar mass. Its molar mass is 18g/mol. The number of moles here is thus 0.18/18 = 0.01moles
But there are 2 atoms of hydrogen in 1 mole of water and thus, the number of moles of hydrogen is 2 * 0.01= 0.02moles
The empirical formula can be obtained by dividing the number of moles of each by the smallest which is that of 0.01
H = 0.02/0.01 = 2
C = 0.01/0.01 = 1
From the calculations, x = 1 and y = 2
The empirical formula is thus CH2
Answer:
The empirical formula is CH2
Explanation:
Step 1: Data given
Burning a hydrocarbon yields 0.18 grams of H2O and 0.44 grams of CO2
Molar mass of CO2 = 44 g/mol
Molar mass of H2O = 18 g/mol
Step 2: Calculate moles
Moles = Mass / molar mass
Moles CO2 = 0.44 grams / 44 g/mol = 0.01 moles
Moles H2O = 0.18 grams / 18 g/mol = 0.01 moles
In CO2 we have 1 mol C
For 0.01 mol CO2 that means we have 0.01 mol C
In H2O we have 2 mol H
For 0.01 mol H2O that means we have 2*0.01 = 0.02 mol H
Step 3: Calculate mol ratio
ratio C:H = 1:2
That means for each C atom we'll have 2 H atom
The empirical formula is CH2
