How many moles of helium gas are contained in a 4.0-L flask at STP?

How can a molecule be nonpolar when it consists of atoms that have different electronegativities?

Which of the following cycles tracks the movement of water in the hydrosphere? A. the hydrologic cycle B. the nitrogen cycle C. the rock cycle D. the hydrogen cycle

5.40 g B how many atoms

Why can water dissolve many substances

The addition of heat energy to a system always causes the temperature of that system to increase. True False

Pedro listed characteristics of two types of protists in a chart. Two Groups of Protists X Y Often multicellular Are usually autotrophic Include euglenoids Are heterotrophs Reproduce using spores Include different molds Which headings best complete

Which of the following is a characteristic of nonmetals? a. nonmetals are often shiny and hard. b. nonmetals are often malleable. c. Nonmetals do not conduct electricity. d. nonmetals are often ductile.

How does a change in temperature affect the kinetic energy of the particles in a reaction?

Which characteristic best identifies an Arrhenius base

Which statement correctly describes why a compound is a pure substance? O A compound is not a pure substance because each of its molecules is m elements A compound is a pure substance because its molecule cannot be broken O A compound is not a pure