1.) 2 methylpropene is a compound used to make synthetic rubber. A sample of 2 methylpropene contains 0.566 g C and 0.0933 g H. Determine its empirical formula
mols C = grams/atomic mass = ?
mols H = grams/atomic mass = ?
Now find the ratio of the two elements to each other with the smaller number being no less than 1.00. The easy way to do is to divide BOTH numbers by the same small number,then multiply both numbers by any number to produce a whole number for C and a whole number for H. That is multiply by 2, 3, 4, etc until you get two whole numbers. The answer here is CH2.
To determine the empirical formula of 2-methylpropene, we need to calculate the ratio of the elements present in the compound.
First, we need to find the moles of carbon and hydrogen in the sample:
Step 1: Calculate the moles of carbon (C):
moles of C = mass of C / molar mass of C
moles of C = 0.566 g / 12.01 g/mol = 0.0471 mol
Step 2: Calculate the moles of hydrogen (H):
moles of H = mass of H / molar mass of H
moles of H = 0.0933 g / 1.01 g/mol = 0.0921 mol
Step 3: Calculate the ratio of moles of carbon to moles of hydrogen:
The ratio is obtained by dividing the moles of each element by the smallest number of moles.
In this case, the smaller value is 0.0471 mol.
moles of C / moles of H = 0.0471 mol / 0.0471 mol = 1
moles of H / moles of H = 0.0921 mol / 0.0471 mol = 1.96
Since we need whole numbers, we can round the ratio to the nearest whole number:
The empirical formula of 2-methylpropene is CH2.
To determine the empirical formula of 2-methylpropene, we need to find the ratio of its elements (C and H).
Step 1: Convert the given masses of carbon (C) and hydrogen (H) into moles.
The molar mass of carbon is 12.01 g/mol, so
moles of carbon = 0.566 g C / 12.01 g/mol ≈ 0.047 moles of carbon
The molar mass of hydrogen is 1.008 g/mol, so
moles of hydrogen = 0.0933 g H / 1.008 g/mol ≈ 0.0923 moles of hydrogen
Step 2: Find the smallest whole number ratio of the atoms by dividing the moles of each element by the smallest number of moles obtained.
Dividing the moles of carbon and hydrogen by 0.047 (the smaller value gives the whole number ratio), we get:
moles of carbon = 0.047 moles of carbon / 0.047 = 1 mole of carbon
moles of hydrogen = 0.0923 moles of hydrogen / 0.047 = 1.96 moles of hydrogen
Since we need to have whole numbers for the empirical formula, we can round the value of 1.96 to the nearest whole number.
Step 3: Write the empirical formula using the ratios obtained.
The empirical formula of 2-methylpropene is CH₂. The ratio of carbon to hydrogen is 1:2.
Thus, the empirical formula of 2-methylpropene is CH₂.