The empirical formula of a compound is CH2. The molecular formula of this compound could be which of the following?

a) CH4 b) C2H2 c) C2H4 d) C2H6

To determine the molecular formula of a compound given its empirical formula, we need to know the molar mass of the compound. However, without this information, we can infer the molecular formula by examining the empirical formula.

The empirical formula CH2 suggests that the compound contains one carbon atom (C) and two hydrogen atoms (H). Now let's consider the options:

a) CH4: The molecular formula CH4 has one carbon atom and four hydrogen atoms. It does not match the empirical formula CH2, as there are more hydrogen atoms present.

b) C2H2: The molecular formula C2H2 has two carbon atoms and two hydrogen atoms. It does not match the empirical formula CH2, as there is an additional carbon atom present.

c) C2H4: The molecular formula C2H4 has two carbon atoms and four hydrogen atoms. This matches the empirical formula CH2, where the carbon atoms are doubled, indicating that this compound is ethene (also known as ethylene).

d) C2H6: The molecular formula C2H6 has two carbon atoms and six hydrogen atoms. It does not match the empirical formula CH2, as there are extra hydrogen atoms present.

From the given options, the molecular formula that matches the empirical formula CH2 is C2H4. Therefore, the correct answer is option c) C2H4.

To determine the molecular formula of the compound with an empirical formula of CH2, we need to know the molar mass of the compound. Without the molar mass, we cannot definitively determine the molecular formula. However, based on the given options, we can make an educated guess.

The empirical formula CH2 implies a compound consisting of one carbon atom and two hydrogen atoms. We can calculate the molar mass of this empirical formula by adding the atomic masses of carbon (C) and hydrogen (H):

Molar mass of CH2 = (1 * atomic mass of C) + (2 * atomic mass of H)

The atomic mass of carbon (C) is approximately 12.01 g/mol, and the atomic mass of hydrogen (H) is approximately 1.01 g/mol.

Therefore, molar mass of CH2 = (1 * 12.01 g/mol) + (2 * 1.01 g/mol)

Simplifying the equation, we get:

Molar mass of CH2 ≈ 14.03 g/mol

Now, let's analyze the given options:

a) CH4: The molar mass of CH4 is (1 * 12.01 g/mol) + (4 * 1.01 g/mol) = 16.05 g/mol, which is greater than the calculated molar mass (14.03 g/mol) of CH2. Therefore, CH4 is not the correct molecular formula for the given empirical formula.

b) C2H2: The molar mass of C2H2 is (2 * 12.01 g/mol) + (2 * 1.01 g/mol) = 26.04 g/mol, which is greater than the calculated molar mass of CH2. Therefore, C2H2 is not the correct molecular formula for the given empirical formula.

c) C2H4: The molar mass of C2H4 is (2 * 12.01 g/mol) + (4 * 1.01 g/mol) = 28.06 g/mol, which is greater than the calculated molar mass of CH2. Therefore, C2H4 is not the correct molecular formula for the given empirical formula.

d) C2H6: The molar mass of C2H6 is (2 * 12.01 g/mol) + (6 * 1.01 g/mol) = 30.08 g/mol, which is greater than the calculated molar mass of CH2. However, since the molar mass of CH2 is approximately 14.03 g/mol, we can infer that it is approximately half the molar mass of C2H6. Therefore, considering the given options, C2H6 is the best choice for the molecular formula of the compound with an empirical formula of CH2.

So, the correct answer is d) C2H6.

C2h2

It can be any multiple of CH2; i.e., (CH2)2; (CH2)3; (CH2)4; etc.