Question

Determine the empirical formula of the following compound if a sample contains 0.104 molK, 0.052 molC, and 0.156 molO;?

Answer 1

The empirical formula of a compound containing 0.104 mol of potassium (K), 0.052 mol of carbon (C), and 0.156 mol of oxygen (O) is K2CO3, based on the smallest whole number ratio of moles of each element.

Step-by-step explanation:

To determine the empirical formula of a compound from the amount of moles of each element, you need to find the smallest whole number ratio of the moles of each element. For the compound mentioned with 0.104 mol K (potassium), 0.052 mol C (carbon), and 0.156 mol O (oxygen), you can do this by dividing each mole value by the smallest of the amounts of moles present.

In this case, the smallest value is 0.052 mol (carbon). So you would divide the number of moles of each element by 0.052 mol:

• K: 0.104 mol / 0.052 mol = 2
• C: 0.052 mol / 0.052 mol = 1
• O: 0.156 mol / 0.052 mol = 3

Therefore, the empirical formula is K2CO3.

Answer 2

K₂CO₃

Step-by-step explanation:

Given parameters:

Number of moles of K = 0.104mol

Number of moles of C = 0.052mol

Number of moles of O = 0.156mol

Method

From the given parameters, to calculate the empirical formula of the elements K, C and O, we reduce the given moles to the simplest fraction.

Empirical formula is the simplest formula of a compound and it differs from the molecular formula which is the actual formula of a compound.

• Divide the given moles through by the smallest which is C, 0.052mol.
• Then approximate values obtained to the nearest whole number of multiply by a factor to give a whole number ratio.
• This is the empirical formula

Solution

Elements K C O

Number of moles 0.104 0.052 0.156

Dividing by the

smallest 0.104/0.052 0.052/0.052 0.156/0.052

2 1 3

The empirical formula is K₂CO₃