How many joules are there in 83.9 cal? Express your answer to three significant figures.

Which weighs more, 0.50 mole oxygen atoms or 4 mole of hydrogen atoms?

Why was galileo sketch in his studies was important?

Where are the longest continuous mountain ranges on Earth located? A. In the Western portion of the United States B. In the Middle East C. Along the San Andreas fault D. Along the ocean floor

Which of the following conditions will result in a reaction that is spontaneous at all temperatures? a. positive enthalpy change and positive entropy change b. negative enthalpy change and positive entropy change c.

What should have only one idependent variable

Which substance is the oxidizing agent in this reaction? 2CuO+C→2Cu+CO2 Express your answer as a chemical formula.

Why does the light bulbs have to be part of the loop in order for it to be succesful?

Which best describes the transition from gas to liquid? Energy must be removed because particles in liquid move more slowly. Energy must be added because particles in liquid move more quickly.

Calculate the mass of a 0.255-ml sample of a liquid with density 0.660 g/ml.

Which statement correctly describes the interaction between magnetic poles? North and south poles attract each other. North and south poles repel each other. Two north poles will attract each other. Two south poles will attract each other.