2. Zn + HCI. ZnCl2 + H2

what reaction is this

Which is the layer underground where all empty spaces are filled with a combination of air and water ?

List four observations that indicate that a chemical reaction may be taking place

Which set of characteristics best describes igneous rock? a) largest type of rock, made of organic matter, hardest type of rock b) least abundant type of rock, made of other rocks, made mostly of minerals c) found on all continents, contains wavy bands of stripes, contains fossils d) most abundant type in earth's crust, made of magma/lava, contains no fossils