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Agroup of students is studying convection current. they fill two identical balloons with the same amount of helium. one balloon is placed in a freezer and the other is in an area with warm air. after 10 minutes, the balloon are released from a height of 1 meter. which of the following to the students most likely observe? a) the warm balloon expands and rises. the cold balloon shrinks and sinks b) the balloon both rise. the cold balloon is larger than the warm balloon c) the cold balloon expands and rises. the warm balloon shrinks and sinks d) the balloon rise at the same rate. both balloons are the same size

What does the symbol (–hfus) indicate in a phase change?

You just calculated that the heat of fusion for chloromethane is 6400 j/mol. the heat of fusion for hydrogen is 120 j/mol.? which of the following account for this difference? more than one correcta. chloromethane can absorb more energy at the same temperature. b. hydrogen has stronger intermolecular forces than chloromethane. c. hydrogen molecules can pack more closely than chloromethane molecules. d. chloromethane experiences dipole-dipole interactions. e. chloromethane has a higher molar mass than hydrogen.