Periodic Table Trends

What happens to the atomic numbers as you move from left to right on the periodic table?

• Increase

• Decrease

• Stay the same

• Nothing

Answer explanation

As you move from left to right on the periodic table, the atomic numbers increase sequentially. Each element has a unique atomic number that corresponds to the number of protons in its nucleus.

Which of the following elements is most likely to have similar properties to those of sodium (Na)?

• Magnesium (Mg)

• Sulfur (S)

• Francium (Fr)

• Titanium (Ti)

Answer explanation

Francium (Fr) is in the same group as sodium (Na) on the periodic table, making it more likely to share similar properties. Both are alkali metals, while magnesium, sulfur, and titanium belong to different groups.

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Two elements that have similar physical and chemical properties are most likely in the same...

• period

• row

• group

Answer explanation

Elements with similar physical and chemical properties are found in the same group (or column) of the periodic table, as they have the same number of valence electrons, which determines their reactivity and properties.

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Which element is most likely to have six valence electrons?

• Barium (Ba)

• Carbon (C)

• Oxygen (O)

• Americium (Am)

Answer explanation

Oxygen (O) has six valence electrons, as it is in group 16 of the periodic table. Barium (Ba) has two, carbon (C) has four, and americium (Am) has three to six depending on its oxidation state.

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Which element is most likely to have three electron energy levels?

• Argon (Ar)

• Lithium (Li)

• Boron (B)

• Europium (Eu)

Answer explanation

Argon (Ar) is in period 3 of the periodic table, indicating it has three electron energy levels. Lithium (Li) and Boron (B) have fewer, while Europium (Eu) has more due to being in a higher period.

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In which group would an element that is not reactive most likely be located?

• 1

• 2

• 16

• 18

Answer explanation

Elements in group 18 are the noble gases, which are known for their lack of reactivity due to having a full valence shell of electrons. Therefore, an element that is not reactive would most likely be located in group 18.

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In which group would an element that is very reactive most likely be located?

• 1

• 5

• 15

• 18

Answer explanation

Elements in Group 1, the alkali metals, are known for their high reactivity, especially with water and halogens. This makes Group 1 the most likely location for very reactive elements.

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In which group would an element that is a gas most likely be located?

• 1

• 3

• 12

• 18

Answer explanation

Elements that are gases at room temperature are typically found in Group 18, the noble gases, which are all gases. Other groups, like 1, 3, and 12, contain metals or metalloids that are not gases.

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Which of the following elements is most likely a poor conductor of electricity?

• Beryllium (Be)

• Gold (Au)

• Phosphorus (P)

• Copper (Cu)

Answer explanation

Phosphorus (P) is a non-metal and typically does not conduct electricity well, making it a poor conductor. In contrast, beryllium, gold, and copper are metals known for their good electrical conductivity.

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Elements in the same column of the periodic table always have the same # of _______ as one another.

• Protons

• Neutrons

• Electrons

• Valence Electrons

Answer explanation

Elements in the same column (group) of the periodic table have the same number of valence electrons, which determines their chemical properties. This is why the correct answer is 'Valence Electrons'.

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