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Question
When a 1.0 M solution of NaCl at 25C is heated to 55C, theA) density decreases and the molarity decreases.
B) density decreases and the molarity increases.
C) density increases and the molarity decreases.
D) density increases and the molarity increases.
Answer
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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.
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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
C) element C
D) element D
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What group of elements is most likely to form covalent molecular hydrides?A) AB) BC) CD) D
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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:
When 3.600 grams of anhydrous magnesium chloride were exposed to moist air, water was absorbed by the sample. If the resulting hydrated compound has a mass of 4.962 grams, what is the chemical formula of the hydrate?
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Q:
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B) H2O2
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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)
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Which transition metal hydride is commonly used in the purification of hydrogen gas?
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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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The strongest homonuclear single bond isA) H-HB) C-CC) N-ND) O-O
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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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How many grams of chromium metal are plated out when a constant current of 8.00 A is passed through an aqueous solution containing Cr3+ ions for 40.0 minutes?
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A steel pipe can be protected from corrosion by attaching the pipe to a piece of magnesium because
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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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