Compared to the atomic radius of a carbon atom, the atomic radius of a silicon atom is larger because of an increase in:
A the number of principal energy levels
B the number of neutrons
C the number of valence electrons
D the nuclear charge

Which of the following signs of a chemical reaction are observed in the reaction of potassium with water? precipitate formed temperature change smell produced gas produced color change

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

Imagine that you push on a large rock. at what point does your effort change the rock’s mechanical energy?