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Question
The following pictures represent solutions at various points in the titration of a weak acid HA with aqueous KOH. Unshaded spheres represent H atoms, black spheres represent oxygen atoms, and shaded spheres represent A- ions. (K+, H3O+ initially present, OH- initially present and solvent water molecules have been omitted for clarity).
Which picture represents the solution before the addition of any KOH?
A) (1)
B) (2)
C) (3)
D) (4)
Answer
This answer is hidden. It contains 1 characters.
Related questions
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In the following picture of an oxide, darkly-shaded spheres represent oxygen atoms or ions and lightly-shaded spheres represent atoms or ions of a third-row element in its highest oxidation state. Tell whether the oxide is covalent or ionic and whether the oxide is acidic or basic. A) covalent and acidic
B) covalent and basic
C) ionic and acidic
D) ionic and basic
Q:
Picture (a) shows p-orbital overlap between carbon and oxygen atoms; picture (b) shows p-orbital overlap between silicon and oxygen atoms. Based on these pictures, it is expected that
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B) silicon and oxygen form better σ bonds than carbon and oxygen, so Si-O single bonds are stronger than C-O single bonds.
C) carbon and oxygen form better π bonds than silicon and oxygen, so C=O double bonds are stronger than Si=O double bonds.
D) silicon and oxygen form better π bonds than carbon and oxygen, so Si=O double bonds are stronger than C=O double bonds.
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Which element shown on the periodic table above forms an interstitial binary hydride with the formula MXx?
A) element A
B) element B
C) element C
D) element D
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B) element B
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The following pictures represent binary hydrides, AHx, where A = Na, Ti, C, or Cl. Lightly-shaded spheres represent H atoms or ions and darkly-colored spheres represent atoms or ions of element A.Which hydride has the lowest melting point?A) hydride (1)B) hydride (2)C) hydride (3)D) hydride (4)
Q:
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Q:
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Q:
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Q:
What is the reaction of potassium peroxide in water?A) 2 KO2(s) + H2O(l) -> O2(g) + 2 K+(aq) + HO2-(aq) + OH-(aq)B) K2O2(s) + H2O(l) -> 2 K+(aq) + HO2-(aq) + OH-(aq)C) 2 K2O2(s) + 2 H2O(l) -> 4 K+(aq) + 4 OH-(aq) + O2(g)D) K2O(s) + H2O(l) -> 2 K+(aq) + 2 OH-(aq)
Q:
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Q:
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Which element most readily forms nonstoichiometric hydrides?
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Covalent hydrides of the type MH3 are likely to form with elements of what group?
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Q:
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Q:
The bright colors of anodized titanium are due toA) electrodeposition of organic dyes on the titanium surface.B) the formation of a titanium alloy with chromium and copper.C) iridescence involving the semitransparent outer layer of TiO2.D) trapping of organic dye molecules in a spongy TiO2 matrix.
Q:
Chromium can be electroplated from an aqueous solution containing sulfuric acid and chromic acid, H2CrO4. What current is required to deposit chromium at a rate of 1.25 g/min?
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Q:
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Q:
A steel pipe can be protected from corrosion by attaching the pipe to a piece of magnesium because
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Q:
Which of the following statements concerning the rusting of iron is false?
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B) The metal is reduced.
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Q:
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