Ch.4 - Chemical Quantities & Aqueous ReactionsWorksheetSee all chapters
All Chapters
Ch.1 - Intro to General Chemistry
Ch.2 - Atoms & Elements
Ch.3 - Chemical Reactions
BONUS: Lab Techniques and Procedures
BONUS: Mathematical Operations and Functions
Ch.4 - Chemical Quantities & Aqueous Reactions
Ch.5 - Gases
Ch.6 - Thermochemistry
Ch.7 - Quantum Mechanics
Ch.8 - Periodic Properties of the Elements
Ch.9 - Bonding & Molecular Structure
Ch.10 - Molecular Shapes & Valence Bond Theory
Ch.11 - Liquids, Solids & Intermolecular Forces
Ch.12 - Solutions
Ch.13 - Chemical Kinetics
Ch.14 - Chemical Equilibrium
Ch.15 - Acid and Base Equilibrium
Ch.16 - Aqueous Equilibrium
Ch. 17 - Chemical Thermodynamics
Ch.18 - Electrochemistry
Ch.19 - Nuclear Chemistry
Ch.20 - Organic Chemistry
Ch.22 - Chemistry of the Nonmetals
Ch.23 - Transition Metals and Coordination Compounds

Solution: In which reaction does the oxidation number of hydrogen change?1) CaO(s) + H2O(l) → Ca(OH)2(s)2) 2Na(s) + 2H2O(l) → 2NaOh(aq) + H2(g)3) SO2(g) + H2O(l) → H2SO3(aq)4) HCl(aq) + NaOH(aq) → NaCl(aq) + H 

Problem

In which reaction does the oxidation number of hydrogen change?

1) CaO(s) + H2O(l) → Ca(OH)2(s)

2) 2Na(s) + 2H2O(l) → 2NaOh(aq) + H2(g)

3) SO2(g) + H2O(l) → H2SO3(aq)

4) HCl(aq) + NaOH(aq) → NaCl(aq) + H 2O(l)

5) HClO4(aq) + CaCO3(s) → Ca(ClO4)2(aq) + H2O(l) + CO2(g)

Solution

We are asked to choose from the given reactions where the oxidation state of hydrogen changed.


We must identify the oxidation state of Hydrogen for each reaction, both in the reactant side and the product side. Let us look at each of the reactions and focus on compounds containing Hydrogen.


View the complete written solution...