A sample consisting of 1.00 mol of Argon is expanded isothermally at 273.15 K from 22.4 L to 44.8 L. Calculate DH, w, and q assuming Argon is an ideal gas and the expansion process is: (a) reversible (b) irreversible, against a constant external pressure equal to the final pressure of the gas (c) irreversible, against zero external pressure (i. e., free expansion) Answer in kJ.

The alkali metals (group 1) consist of lithium (3), sodium (11), potassium (19), rubidium (37), cesium (55), and francium (87). they are soft, metallic solids with low densities and low melting points. based on the data shown in figure 1, how many valence electrons do alkali metals share?

Which statement names the physical property of wood a. wood is softer than coal b. wood does not rust c. wood can rot d. wood can burn

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?