Select the correct answer. why does every chemical reaction require a certain amount of activation energy? a. energy is released when the reactants begin to react. b. energy lost to the environment during the reaction must be replaced. c. forming the activated complex requires energy. d. the products have more potential energy than the activated complex. e. the reactants have less potential energy than the products.

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?

Based on the equation, how many grams of br2 are required to react completely with 29.2 grams of alcl3? alcl3 + br2 → albr3 + cl2 48.7 grams 52.6 grams 56.7 grams 61.3 grams

The atomic number of an element is based on the number of electrons around its core mass of its nucleus number of protons in its nucleus number of neutrons in its nucleus