Periodic Table Quiz

Which of the following statements best explains why Dobereiner's law of triads failed for many known elements?

• The atomic weights were inaccurately measured.

• It only applied to elements with small atomic masses.

• Many elements had atomic weights that were not averages of the first and third elements in a triad.

• The properties of elements were more correlated to atomic numbers than atomic weights.

How did Mendeleev predict the existence of elements that were not yet discovered?

• By assuming all elements had the same valency.

• By leaving blank spaces for missing elements based on atomic weight trends.

• By observing electron configurations in existing elements.

• By applying Newlands' law of octaves to ungrouped elements.

According to the modern periodic law, which of the following properties is periodic when elements are arranged by atomic number?

• Atomic Mass

• Atomic Weight

• Chemical Properties

• Number of Neutrons

In which of the following groups would you most likely find metalloids?

• Group 1

• Group 14

• Group 17

• Group 2

The reason that chlorine (Cl) is smaller than sulfur (S) despite being further right on the periodic table is:

• Sulfur has more electron shells.

• Chlorine's electrons experience a greater effective nuclear charge.

• Chlorine is a non-metal, while sulfur is a metalloid.

• The electron affinity of chlorine is greater than that of sulfur.

Which factor primarily causes ionization energy to increase across a period?

• Decreasing atomic radius

• Increasing shielding effect

• Increasing number of shells

• Decreasing nuclear charge

Which of the following elements has the highest electronegativity?

• Fluorine

• Nitrogen

• Oxygen

• Chlorine

Which of the following would most likely have the largest atomic radius?

• Potassium (K)

• Sodium (Na)

• Rubidium (Rb)

• Cesium (Cs)

What does Mendeleev's placement of tellurium (Te) before iodine (I) despite higher atomic weight suggest about his table?

• Atomic number is a better organizing principle than atomic mass.

• Tellurium is incorrectly classified.

• Iodine has chemical properties more similar to group 16.

• Mendeleev was unaware of atomic weights.

Why do elements in the same group have similar chemical properties?

• They have the same number of neutrons.

• They have similar atomic masses.

• They have the same valence electron configuration.

• They belong to the same period.