Chemical properties of radium are its high reactivity and that it continuously breaks down and changes into other elements. Most radium isotopes, or atoms that have a different number of neutrons than the normal radium atom, are unstable and radioactive.
The half-life of radium's most stable isotope, 226, is 1600 years. During that time, it decays into radon and produces ionizing radiation. These are alpha, beta and gamma particles.
Alpha particles are simply the nuclei of helium atoms. They are positively charged and are easily to deflect. Beta particles are high speed electrons that can be deflected by electric and magnetic fields. Gamma rays are types of electromagnetic radiation and are not affected by electrical fields.