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Which solution reacts with potassium iodide to form a precipitate? A. Pb(ClO4)2 B. Ca(NO3)2 C. NH4Cl D. NaNO3

What happens when the system changes from A to B?   A. endothermic condensing process B. exothermic condensing process C. endothermic melting process D. exothermic melting process

Dinitrogen tetraoxide, N2O4, decomposes to nitrogen dioxide, NO2, in a first-order process. If k = 2.5 × 103 s–1 at 268 K and k = 3.5 × 104 s–1 at 298 K, what is the activation energy for the decomposition? A.  0.73 kJ/mol B. 140 kJ/mol C. 58 kJ/mol D. 580 kJ/mol

How much heat is required to warm 1.50 L of water from 25.0

The vapor pressure of substance X is higher than that of substance Y at 298 K.  This observation means that A. X has stronger intermolecular forces than Y. B. Y has stronger intermolecular forces than X. C. X and Y have intermolecular forces of the same strength. D. The relative strength of the intermolecular forces cannot be determined.

How many moles of Carbon atoms are present in 2.50 g of Glucose (C6H12O6). MW C6H12O6 = 180.18 g/mol A. 0.0138 mol C B. 0.0416 mol C C. 0.0833 mol C D. 12.0 mol C

An equilibrium mixture contains 0.200 moles CH3OH, 0.400 moles CO and 0.500 moles H2 in a 2.0 L container.  What is the equilibrium constant (Kc) for the reaction?   A. 2.00 B. 0.500 C. 1.00 D. 0.125

Element X reacts with Sodium to form the ionic compound Na2X.  What is element X if its anion has 18 electrons? A. S B. Ar C. Se D. Br    

A photon of infrared light has a ____________________________ wavelength and ______________________ energy than a photon of ultraviolet radiation.   A. Shorter, lower B. Longer, lower C. Shorter, higher D. Longer, higher

What is the oxidation state of manganese in MnO4-? A.  +1 B.  +3 C.  +5 D.  +7