Dãy chất nào sau đây chỉ gồm các oxit axit: * A. CO2, CaO, MgO
B. H2O, MgO, SO2
C. CO2, P2O5 , N2O5
D. ZnO, Fe2O3, SO3

Scientists often have to deal with numbers that are either very large or very small. for example, the radius of the sun is approximately 696,000 kilometers, while bacterial cells are as small as 1.9 × 10-4 millimeters. express each number in an alternate form.

Mercury turns to a vapor at 629.88 k. how much heat is lost when 75.0 g of mercury vapor at 650 k condenses to a liquid at 297 k?

What are several ways to reduce the effect of friction