How many moles of hydrogen are present in a 2.76 L sample of acetylene gas (C2H2) at STP?

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

According to the vsepr theory what is the shape of a molecule that has a central atom valence three other items with no lone pairs of electrons

Drug abuse will not lead to physical and psychological dependence. true or false ?