Did the Industrial Revolution in the 19th century lead to widening differences between north and south?

Answer 1

Yes.

The North began to industrialise with enthusiasm, while the South stayed in its traditional feudal state, living off cotton.

When the North wanted to protect its manufacturing industries by raising the tariff against imported goods (which the South needed), the South saw it as a direct tax on them, made possible by the Northern majority in Congress.

When it came to admitting new states to the Union, the South wanted more slave-states, to balance things up, while North wanted more free-soil states, to maintain their majority.