Volcanic molten lava pours out and re-hardens back into the rock again. Chemical change or physical change?

Match the following items. 1. high-intensity bundle of energy being emitted from some decaying nuclei gamma ray 2. particle radiating from the nucleus of some atoms beta particle 3. negative particle identical to an electron but radiating from a decaying nucleus alpha particle

What is the empirical formula of c6h18o3? ch3o c2h5o c2h6o c2h5o5

Great amounts of electromagnetic energy from our sun and other bodies in space travel through space. which is a logical conclusion about these electromagnetic waves? their energy must be very their frequency must be very low these waves can travel without a medium they only travel through a vacuum of space