Agraduated cylinder contains 15.75 ml of water. a metal that weighs 31.745 g is added. the final reading is 38.55 ml. using the correct number of significant figures, determine the density of the metal = g/ml first determine volume of metal: report result to the same number of decimal places as the number with the least number of decimal places. use this volume in calculation. second determine density of metal: d=m/v report result to the same number of significant figures as the number with the least number of significant figures. do not use exponential notation in answer.

Water (2510 g ) is heated until it just begins to boil. if the water absorbs 5.09×105 j of heat in the process, what was the initial temperature of the water?

Two nitro no2 groups are chemically bonded to a patch of surface. they can't move to another location on the surface, but they can rotate (see sketch at right). it turns out that the amount of rotational kinetic energy each no2 group can have is required to be a multiple of ε, where =ε×1.010−24 j. in other words, each no2 group could have ε of rotational kinetic energy, or 2ε, or 3ε, and so forth — but it cannot have just any old amount of rotational kinetic energy. suppose the total rotational kinetic energy in this system is initially known to be 32ε. then, some heat is removed from the system, and the total rotational kinetic energy falls to 18ε. calculate the change in entropy. round your answer to 3 significant digits, and be sure it has the correct unit symbol.

What is a substance? a. a physical property of matter b. a chemical property of matter c. an element or compound that cannot be physically separated d. characteristics used to tell the difference between mixtures