Achemist is studying an unknown substance. he can break it into its elemental components only by using chemical means.

based on this observation, how should the unknown substance be classified?
a. impure substance

b. solution

c. mixture

d. pure substance

Estimate the kinetic energy of the neptune with respect to the sun as the sum of the terms, that due to its daily rotation about its axis, and that due to its yearly revolution about the sun. [assume the neptune is a uniform sphere with mass = 1.0×1026 kg , radius = 2.5×1010 m , rotation period 16.1 h , orbital period 6.01×104 d and is 4.6×109 km from the sun.]