An equimolar mixture of X (g) and Y (g) is placed inside a rigid container at constant temperature. The particle diagram above represents the changes that occur over time. Based on the particle diagram, which of the following best predicts whether or not the system has reached equilibrium by 300 s?
a. It is not possible to determine that the system has reached equilibrium by 300 s because the stoichiometry of the reaction is not known.

b. it is not possible to determine that the system has reached equilibrium by 300 s because the amounts of X, Y, and XY have continued to change

c. The system has reached equilibrium by 300 s because the rate of formation of XY is constant
d. The system has reached equilibrium by 300 s because the rates of consumption of X and Y are equal

The image compares the arrangement of electrons in two different neutral atoms. a figure labeled atom q has a shaded sphere at the center of three concentric circles. the innermost circle has two black spheres. the middle circle has six black spheres. to the left of this figure is another figure labeled atom p. atom p has a shaded sphere at the center of three concentric circles. the innermost circle has two black spheres. the middle circle has seven black spheres. which of the following best explains the position of the two atoms in the periodic table? atom p has an estimated zeff of 7 and is therefore to the left of atom q, which has a zeff of 6. atom p has an estimated zeff of 7 and is therefore to the right of atom q, which has a zeff of 6. atom p has an estimated zeff of 5 and is therefore below atom q, which has a zeff of 4. atom p has an estimated zeff of 5 and is therefore above atom q, which has a zeff of 4.