Elements Practice Quiz

  1. Which element is found in potassium chlorate and zinc nitrate?
  1. Hydrogen
  2. Oxygen
  3. Potassium
  4. Zinc
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The correct answer is B!

KClO3 and Zn(NO3)2 both contain oxygen, so oxygen is present in both compounds.

 

  1. Atoms of which element have the weakest attraction for electrons?
  1. Na
  2. P
  3. Si
  4. S
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The correct answer is A!

Sodium has the lowest electronegativity among Na, P, Si, and S, so it attracts electrons most weakly.

 

  1. Which element is classified as a metalloid?
  1. Sulfur
  2. Silicon
  3. Barium
  4. Bromine
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The correct answer is B!

Silicon is a metalloid with properties intermediate between metals and nonmetals.

 

  1. Which metal is most likely obtained by the electrolysis of its fused salt?
  1. Au
  2. Ag
  3. Li
  4. Zn
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The correct answer is C!

Very reactive metals, like Li, are obtained by electrolysis of their molten salts rather than chemical reduction.

 

  1. Because of its high reactivity, which element is never found free in nature?
  1. O
  2. F
  3. N
  4. Ne
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The correct answer is B!

Fluorine is so reactive that it occurs only in compounds, never as free F2 in nature.

 

  1. Why does iron corrode more easily than aluminum and zinc?
  1. Aluminum and zinc are both reduced
  2. Aluminum and zinc are both oxidizing agents
  3. Aluminum and zinc both form oxides that are self-protective
  4. Aluminum and zinc both form oxides that are very reactive
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The correct answer is C!

Aluminum and zinc form dense, adherent oxide layers (Al2O3, ZnO) that protect the metal. Iron’s oxide does not.

 

  1. Which substance is produced by the Haber process?
  1. Aluminum
  2. Ammonia
  3. Nitric acid
  4. Sulfuric acid
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The correct answer is B!

The Haber process synthesizes ammonia:

\(\text{N}_2 + 3\text{H}_2 \rightleftharpoons 2\text{NH}_3\)

 

  1. What is the total number of moles of hydrogen atoms contained in one mole of (NH4)2C2O4?
  1. 6
  2. 2
  3. 8
  4. 4
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The correct answer is C!

(NH4)2C2O4 has two NH4⁺ groups times 4 H each, which equals 8 moles of H atoms per mole of compound.

 

  1. The observed regularities in the properties of elements are periodic functions of their…
  1. Atomic numbers
  2. Mass numbers
  3. Oxidation states
  4. Non-valence electrons
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The correct answer is A!

When elements are arranged by increasing atomic number (Z), their valence-shell electron configurations repeat at regular intervals, so properties recur in patterns. Mass number, oxidation state, and non-valence electrons don’t cause the periodic pattern—they’re consequences of position set by Z.

 

  1. Which physical characteristic of a solution may indicate the presence of a transition element?
  1. Density
  2. Color
  3. Effect on litmus
  4. Effect on phenolphthalein
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The correct answer is B!

Many transition-metal ions form colored solutions due to d–d electron transitions.

 

  1. Which element has a crystalline lattice composed of positive ions through which electrons flow freely?
  1. Bromine
  2. Calcium
  3. Carbon
  4. Sulfur
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The correct answer is B!

Metals like calcium have a lattice of positive ions with a “sea” of delocalized electrons that conduct.

 

  1. Red litmus paper will turn blue when placed in an aqueous solution of…
  1. KCl
  2. KOH
  3. CH3OH
  4. CH3COOH
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The correct answer is B!

KOH is a strong base, and bases turn red litmus blue.

 

  1. Equilibrium is attained in a chemical cell when cell voltage is equal to…
  1. +1.00 V
  2. +2.00 V
  3. 0.00 V
  4. -1.00 V
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The correct answer is C!

At equilibrium, \(\Delta G = 0\) and the cell’s net potential is \(E = 0.00 V\).