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Which element requires the least amount of energy to remove the most loosely held electron from a gaseous atom in the ground state?*
As the elements in Period 2 are considered in order from lithium to fluorine, there is an increase in the*
As the first five elements in Group 14 are considered in order from top to bottom, there are changes in both the*
As the elements in Period 2 of the Periodic Table are considered in order from left to right, which property generally decreases?*
Which ion has the largest radius?*
Based on Table S, which group on the Periodic Table has the element with the highest electronegativity?*
Which trend is observed as the first four elements in Group 17 on the Periodic Table are considered in order of increasing atomic number?*
Which group on the Periodic Table has two elements that exist as gases at STP?*
Which general trends in atomic radius and electronegativity are observed as the elements in Period 3 are considered in order of increasing atomic number?*
Base your answers to questions 10 on the information below and on your knowledge of chemistry.
Radioactive emissions can be detected by a Geiger counter. When radioactive emissions enter the Geiger counter probe, which contains a noble gas such as argon or helium, some of the atoms are ionized. The ionized gas allows for a brief electric current. The current causes the speaker to make a clicking sound. To make sure that the Geiger counter is measuring radiation properly, the device is tested using the radioisotope Cs-137.
To detect gamma radiation, an aluminum shield can be placed over the probe window, to keep alpha and beta radiation from entering the probe. A diagram that represents the Geiger counter is shown below.
Compare the first ionization energy of argon to the first ionization energy of helium.*
Base your answers to questions 11 on the information below and on your knowledge of chemistry.
Periodic trends are observed in the properties of the elements in Period 3 on the Periodic Table. These elements vary in physical properties, such as phase, and in chemical properties, such as their ability to lose or gain electrons during a chemical reaction.
State the general trend in atomic radius as the elements in Period 3 are considered in order of increasing atomic number.*
Base your answers to questions 12 on the information below and on your knowledge of chemistry.
The elements in Group 2 on the Periodic Table can be compared in terms of first ionization energy, electronegativity, and other general properties.
Explain, in terms of atomic structure, why barium has a lower first ionization energy than magnesium.*
State the general trend in first ionization energy as the elements in Period 3 are considered from left to right.*
Base your answers to questions 14 on the information below and on your knowledge of chemistry.
Rubidium and iodine have different chemical and physical properties. Some of these properties are shown in the table below.
Compare the atomic radius of an atom of iodine to the atomic radius of an atom of rubidium when both atoms are in the ground state.*
Base your answers to questions 15 on the information below and on your knowledge of chemistry.
Many scientists made observations of the elements that led to the modern Periodic Table. In 1829, Dobereiner found groups of three elements that have similar properties and called each of these groups a triad. Dobereiner noticed a relationship between the atomic masses of the elements in each triad. Triad 1, shown in the table below, consists of sulfur, selenium, and tellurium. The middle element, selenium, has an atomic mass that is close to the sum of the atomic masses of sulfur and tellurium, divided by 2.
The other triads shown in the table below demonstrate the same mathematical relationship.
State the trend in first ionization energy as the elements in triad 3 are considered in order of increasing atomic number.*