Final answer:
The electronegativity difference in H2O is 1.24.
Step-by-step explanation:
When determining the electronegativity difference in a molecule, we compare the electronegativity values of the two atoms involved in the bond. In the case of H2O, hydrogen has an electronegativity of 2.20 and oxygen has an electronegativity of 3.44. To calculate the electronegativity difference, we subtract the electronegativity of the hydrogen atom from the electronegativity of the oxygen atom: 3.44 - 2.20 = 1.24. Therefore, the electronegativity difference in H2O is 1.24.