Passive wireless sensors can be used to detect chemical or biological agents without the use of probes or wires and without the use of a battery. This paper presents a platform used as a passive wireless sensor to detect certain chemicals of interest. The wireless sensor is powered through an interrogator which sends magnetic/inductive waves to the remote sensor. The sensor converts the power to direct current and then sends back a portion of the power through radio frequency waves with altered frequency, amplitude, and phase. The characteristics of the received signal contain the information about the agent of interest.