The magnitude of the impedance |Z| of a capacitor and also the equivalent series resistance (ESR) vary with frequency.
This phenomenon is called the "frequency characteristics."
The frequency characteristics of a capacitor differ greatly from one type of capacitor to another. At high frequencies, a multilayer ceramic capacitor has low impedance and exhibits excellent frequency characteristics. Even multilayer ceramic capacitors come in a variety of types depending upon the raw materials used and the shape of each capacitor. For more details of the effect of these factors on the frequency characteristics, refer to the following: http://www.murata.com/products/emicon_fun/2013/02/cap_en14.html