Which of the following processes absorbs heat? a. Dry ice sublimates at room temperature to form \( \mathrm{CO}_{2} \) gas. b. \( \mathrm{NH}_{3} \) gas condenses under a cold bath of \( -35^{\circ} \mathrm{C} \) to the liquid form. c. Liquid glacial acetic acid freezes in an ice-water bath. d. Iodine vapor captured in a jar forms crystalline iodine when it contacts the cooler lid.

How many oxygen atoms are located on the reactant side of the following chemical equation? \( \mathrm{C}_{3} \mathrm{H}_{8}(\mathrm{~g})+5 \mathrm{O}_{2}(\mathrm{~g}) \rightarrow 3 \mathrm{CO}_{2}(\mathrm{~g})+4 \mathrm{H}_{2} \mathrm{O}(\mathrm{g}) \)

\( 2 LiOH ( s ) \rightarrow Li 2 O ( s ) + H 2 O ( l ) \)

Balance the following chemical equation (if necessary): \[ \mathrm{Ca}(\mathrm{s})+\mathrm{O}_{2}(\mathrm{~g}) \rightarrow \mathrm{CaO} \text { (s) } \]

Значение ЭДС гальванического элемента, состоящего из ртутного и кадмиевого электродов при стандартных условиях равно_B ( \( \left(^{0} \mathrm{Mg}^{2+} / \mathrm{Mg}=-2,38 \mathrm{~B}, \mathrm{E}^{0} \mathrm{Cu}^{2+} / \mathrm{Cu}=0,34 \mathrm{~B}\right) \).

Consider the reaction represented \( \mathrm{byCr}_{2} \mathrm{O}_{7}^{2-}+\mathrm{Cl}^{-} \xrightarrow{\text { i. Explain why the reaction is a redox reaction. }} \quad \mathrm{Cr}^{3+}+\mathrm{Cl}_{2} \) iii. Balance the redox equation State five physical properties of metals