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Two acid-base equilibria are shown. Equation 1: HCN(aq) + H2O(l) ⇌ CN−(aq) + H3O+(aq) Equation 2: NH3(aq) + H2O(l) ⇌ NH4+(aq) + OH−(aq) Which option correctly describes the role of water in each forward reaction? A. In equation 1 water…
Which of these reactions will occur spontaneously? I. KI + Br2 II. KBr + Cl2 III. KCl + Br2 A. I and II only B. I and III only C. II and III only D. I, II and III
Sulfuric acid reacts with solid copper(II) oxide. Which salt is formed? A. CuSO3 B. CuSO4 C. Cu2SO4 D. H2O
The pH of a dilute aqueous solution at 25 °C increases from 4.0 to 6.0. How do the concentrations of hydrogen ions and hydroxide ions change? A. [H+] decreases 100 times and [OH−] increases 100 times B. [H+] decreases 10 times and…
Which combination is correct for this cell, when nickel is more reactive than silver? A. Cathode: silver; anode: nickel; sign on cathode: -; sign on anode: + B. Cathode: nickel; anode: silver; sign on cathode: -; sign on anode: + C. Cathode: nickel; anode:…
What is the conjugate acid of the hydrogencarbonate ion, HCO3−? A. CO32− B. CO2 C. H2CO3 D. H3O+
Both of the reactions below occur spontaneously at room temperature. Zn(s) + Fe2+(aq) → Zn2+(aq) + Fe(s) Fe(s) + Sn2+(aq) → Fe2+(aq) + Sn(s) Which conclusion can be drawn about a voltaic cell built from the half-cells…
What are the products of the electrolysis of molten lead(II) bromide? A. Product at cathode: lead; product at anode: bromine B. Product at cathode: lead; product at anode: bromide C. Product at cathode: bromine; product at anode: lead D. Product at cathode:…
Which species can act as both a Brønsted–Lowry acid and a Brønsted–Lowry base? A. NH4+ B. CO32− C. HPO42− D. Na+
When heated under reflux with excess acidified potassium dichromate(VI), how many of the structural isomers of the alcohol C5H11OH are oxidized to a carboxylic acid? A. 3 B. 7 C. 4 D. 8