What would happen if the attractive forces between all of the particles
of matter on Earth were equal?

The magnitude of attractive forces between particles that compose matter determine the state of matter. Hence, if all particles of matter on earth have equal attractive forces, only a single state of matter (solid, liquid or gas) will exist on earth.

Matter exists in three states;

In solids, there exists the greatest magnitude of attractive forces between particles.

There are weaker inter-molecular attractive forces between liquid particles. However, inter molecular attractive  forces are almost non-existent in gases.

The reason for the existence of different states of matter on earth is difference in magnitude of inter molecular attractive forces in each state of matter.

If all particles of matter possess equal attractive forces, only one state of matter will be found on earth; either solid, liquid or gas.

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