Question

"A cloud of gas and dust in space, called nebula, began to rotate and condensed into a flattened disk. Gravitational force pulled the gas and dust closer together. This resulted in the nuclear fusion of gases and dust to create the sun and planets at the outer flattened portion of the disk." What is the flaw in the student's explanation?

Answer 1

nuclear fission created the sun and planets
the nebula evaporated instead of condensing
the sun was formed at the center of the nebula
gravitational forces kept the gases well separated

Answer 2

The sun would have had to form in the center of the nebula. The solar nebula model youu are referencing only had the planets forming in the outer disk, while the sun froms in the inner disk. If you think intuitively while seeing the solar system, the sun is at the center of the solar system. If the solar system was formed according to what said above, most of the mass of the cloud would have had to settle in the sun, and since we see the Sun in the center, then the sun would have had to form in the inner parts of the cloud.