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Questions in chemistry

[Done] What happens when the electron moves from the first energy level to the second energy level?

[Done] 3.2 The redox reaction below is used to construct an electrochemical cell. [tex]Fe^{2+}(aq) + Ag^{+}(aq) \rightarrow Ag(s) + Fe^{3+}(aq)[/tex] 3.2.1 Define oxidation in terms of oxidation number. 3.2.2 Name a substance that should be used as electrode in the anode half-cell. 3.2.3 Write down the NAME or FORMULA of the oxidizing agent. 3.2.4 Write down the cell notation of the cell.

[Done] Select the correct answer. What is the formula of the compound vanadium(V) oxide? Use the list of polyatomic ions and the periodic table to help you answer. A. $VO _2$ B. $VO _5$ C. $V _5 O _2$ D. $V _2 O _5$ E. $V _2 O _2$

[Done] Consider the following intermediate chemical equations. [tex] \begin{array}{l} C(s)+\frac{1}{2} O_2(g) \rightarrow CO(g) \\ CO(g)+\frac{1}{2} O_2(g) \rightarrow CO_2(g) \end{array} [/tex] When you form the final chemical equation, what should you do with CO? A. Cancel out CO because it appears as a reactant in one intermediate reaction and a product in the other intermediate reaction. B. Add the two CO molecules together, and write them as reactants in the final chemical reaction. C. Write CO only once as a reactant in the final chemical reaction. D. Write CO as a reactant and a product in the final chemical reaction.

[Done] 2,2-dimethyl-1-pentanol, 2-methyl-2-pentanol and 2-methyl-3-pentanol are: A. Primary alcohol, secondary alcohol and tertiary alcohol, respectively B. Secondary alcohol, primary alcohol and tertiary alcohol, respectively C. Tertiary alcohol, secondary alcohol and primary alcohol, respectively D. Primary alcohol, tertiary alcohol and secondary alcohol, respectively

[Done] An electric device delivers a current of [tex]$15.0 A$[/tex] for 30 seconds. How many electrons flow through it?

[Done] GAS-EVOLUTION REACTIONS 7) [tex]HCl (aq)[/tex] and [tex]Na_2S(aq)[/tex] [tex]2 HCl (aq) + Na_2S(aq) \rightarrow H_2S_1(g)[/tex] Molecular Equation Complete Ionic Equation Net Ionic Equation Spectator Ions

[Done] Consider the following intermediate chemical equations: [tex]$\begin{array}{l} CH_4(g)+2 O_2(g) \rightarrow CO_2(g)+2 H_2 O(g) \ 2 H_2 O(g) \rightarrow 2 H_2 O(l) \end{array}$[/tex] Which overall chemical equation is obtained by combining these intermediate equations? A. [tex]$CH _4(g)+2 O _2(g) \rightarrow CO _2(g)+2 H _2 O ( I )$[/tex] B. [tex]$CH _4(g)+2 O _2(g) \rightarrow CO _2(g)+2 H _2 O ( g )$[/tex] C. [tex]$CH _4(g)+2 O _2(g) \rightarrow CO _2(g)+4 H _2 O ( g )+2 H _2 O ( l )$[/tex] D. [tex]$CH _4(g)+2 O _2(g) \rightarrow CO _2(g)+ BH _2 O ( g )$[/tex]

[Done] How is the equilibrium constant of a reaction determined? The molarity of products is multiplied by the molarity of reactants.

[Done] The number of valence electrons in an element with electron configuration [tex]$1 s^2 2 s^2 2 p^6 3 s^2 3 p^4$[/tex] is A. 6 B. 8 C. 4 D. 2 E. 16