Hydrogen iodide decomposes as 2hl > h2 + i2. the average reaction rate is expressed as: average rate - delta[hi]/delta, the negative sign used in the rate expression indicates that: a) there are repulsive forces between the reactants. b) the concentration of hl decreases with time. c) the concentration of the reactants is less than that of the product d)) the reaction rate is decreasing with time

Option C. The concentration of the reactants is less than that of the product d

Explanation:

ca has a crystalline lattice with positive ions (since it is a metal, metals are positively charged) and electrons flow freely in its structure since the ca atoms have a large nuclear radius so the electrons are not tightly held, therefore the electrons can flow freely since they are not being highly attracted by the nucleus. moreover, one of the properties of metals are that they are conductors of electricity, thus proving ca is the element.