Final answer:
To find the number of hydrogen atoms in a 12-carbon linear alkane, we use the formula CnH2n+2, and thus the molecule will have 26 hydrogen atoms, expressed as C12H26.
Step-by-step explanation:
When determining the number of hydrogen atoms in a linear alkane with 12 carbon atoms, we apply the general alkane formula CnH2n+2. The number of hydrogen atoms in an alkane can be calculated by substituting the number of carbon atoms, n, into this formula, thus having the molecular formula C12H(2 × 12) + 2. Therefore, a 12-carbon alkane would have C12H26, meaning it contains 26 hydrogen atoms.
This follows the principle of homology, which is a key concept in organic chemistry describing compounds in a series that differ by a repeating unit, such as in alkanes where each compound differs by a CH2 group. Taking the example of ethane, which has a molecular formula of C2H6, its alkane homolog with 12 carbon atoms will maintain the same hydrocarbon ratio determined by the formula, ensuring there are always enough hydrogen atoms to allow each carbon atom to make four covalent bonds.