Atoms of most elements are less likely to react when they have A. 2 valence electrons
B. 4 valence electrons
C. 6 valence electrons
D. 8 valence electrons

Match the atomic particles with their characteristics. 1. made of two protons and two neutrons neutron 2. similar to an electron; positive charge neutrino 3. orbits nucleus; negative charge positron 4. bundle of energy; zero charge proton 5. found in nucleus; positive charge meson 6. very unstable; +, -, or zero charge gamma 7. found in nucleus; zero charge electron 8. negative particle; negative charge beta 9. atomic energy converted to mass alpha

Astronomers discover an exoplanet (a planet of a star other than the sun) that has an orbital period of 3.87 earth years in its circular orbit around its sun, which is a star with a measured mass of 3.59 x 1030 kg. find the radius of the exoplanet's orbit.

Why do electron microscopes have higher resolving power than light microscopes?