Question

If the earth and sun was made of only neutrons, would there be any effect on the gravitational attraction between them or earths orbit?

Answer 1

of course , because gravitational attraction depend on mass .

yeah, gravitational force does depend on mass, but neutron is what constitutes mainly the mass of an atom. Even if the mass sort of differs, will there be any effect such as the earth not rotating and revolving around sun at all?

If you assume the mass is the same, then the gravitational force would be the same. If you assume the volume stayed the same, you would create a giant blackhole due to increased density. The question is probably just getting at the fact that the electromagnetic interactions between Sol and Earth are nearly zero compared to gravity, so eliminating charge from the system would have essentially no effect