You are measuring the density of an irregularly shaped solid. Direct weighing gives a mass of 31.2789 grams. After placing the object in a graduated cylinder, the volume reading increased from 14.2 mL to 25.9 mL. What is the density of the object

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Amixture that has two or more substances that are spread out evenly is called a. compound b. heterogeneous c. substance d. homogeneous

Consider hydrogen in an excited state n = 5n=5 that emits photons to reach the ground state. there are various possible transitions other than straight to the ground state that can occur; for example, it can drop to the n = 3n=3 state followed by the n = 3n=3 to the ground state transition. which of the possible transitions will result in the emission of a photon in the visible region?