Which of the following best describes how chemical changes differ from physical changes?
A. Physical changes produce no new substances and chemical changes do.
B. Physical changes always involve the formation of a gas while chemical changes may not.
C. Physical changes can occur inside or outside the substance; chemical changes always occur outside.
D. Physical changes involve a change of state; chemical changes involve a change of shape.

Esure to answer all parts. the equilibrium constant for the reaction ni2+(aq) + 6 nh3(aq) ⇌ ni(nh3)6 2+(aq) is kf = 5.6 × 108 at 25°c. (a) what is δg o at this temperature? (b) if standard-state concentrations of reactants and products are mixed, in which direction does the reaction proceed? (c) determine δg when [ni(nh3)62+] = 0.010 m, [ni2+] = 0.0010 m, and [nh3] = 0.0050 m. in which direction will the reaction proceed to achieve equilibrium? (a) × 10 j/mol (enter your answer in scientific notation.) (b) to the right. to the left. (c) × 10 j/mol (enter your answer in scientific notation.) to the right. to the left.