Is the concentration of reactants equal to the concentration of products in a dynamic equilibrium?
No, concentration of reactants and products are not necessarily equal in a dynamic equilibrium.
Equilibrium occurs for a reversible reaction. Reversible means that as reactants bump into each other and become product, products eventually accumulate and bump into themselves, reacting to reform reactants. Equilibrium is reached when system is no longer visibly changing. That point is not reached when there is equal amount of products and reactants, but rather when the rate at which products are made is equal to the rate at which reactants are made.