Each horizontal row on the periodic table is called a (#1: group/period). Each vertical column on the periodic table is called a (#2: group/period). In general, in the periodic table, elements with the same (#3: electron/proton) configuration of the outermost levels have similar properties and are arranged into groups of three types: A – _ (#4: representative/transition) elements, B – _ (#5: representative/transition) elements and _ (#6: noble/nobel) gases.
Elements in the same (#7: group/period) contain the same number of valence electrons in their ground state. They are located vertically on the periodic table. Elements with the same number of principal energy levels are arranged in a (#8: group/period). Metals are situated in the first (#9: 2/8) groups of elements and in the middle of the table. Gases and nonmetals in general are placed into _ (#10: top-right/bottom-right) corner of the table.
Moving from (#11: left/right) to (#12: left/right) in any period of elements, the atomic number increases by one from one element to the next and the atomic radius generally (#13: increases/decreases). Each period (except period 1) begins with an (#14: alkaline/transition) metal and ends with a (#15: noble/halogen) gas. There is a trend in properties of the elements changing from (#16: metallic/nonmetallic) to _ (#17: metallic/nonmetallic) from the beginning to the end of the period.
All of the gases on the periodic table are (#18: nonmetals/noble). All of them have s or p valence orbitals. All of them belong to the _ (#19: representative/transition) elements.All metals are solids except mercury, which is a liquid. All non-gaseous non-metals are solid except bromine, which is a liquid. Therefore, liquids and solids show no pattern for location on the periodic table.
The Correct Answer and Explanation is :
Here are the correct answers for each blank:
- Period
- Group
- Electron
- Representative
- Transition
- Noble
- Group
- Period
- 2
- Top-right
- Left
- Right
- Decreases
- Alkaline
- Noble
- Metallic
- Nonmetallic
- Noble
- Representative
Explanation:
- Period: The horizontal rows in the periodic table are called periods. As you move across a period, the atomic number increases.
- Group: The vertical columns in the periodic table are called groups. Elements in the same group have similar chemical properties.
- Electron: The elements with the same electron configuration in their outermost shells tend to have similar properties.
- Representative: The representative elements (groups 1, 2, and 13-18) have s or p electrons in their outer shell.
- Transition: Transition elements (groups 3-12) generally have d electrons in their outer shells.
- Noble: Noble gases (group 18) are inert due to their stable electron configuration.
- Group: Elements in the same group have the same number of valence electrons.
- Period: Elements in the same period have the same number of energy levels (shells).
- 2: Metals are generally found in groups 1 and 2 as well as the transition elements.
- Top-right: Nonmetals and gases are generally found in the top-right corner of the periodic table.
- Left: Moving from left to right, atomic number increases by one.
- Right: The atomic number increases as you move to the right across a period.
- Decreases: As you move across a period from left to right, the atomic radius generally decreases due to increasing nuclear charge.
- Alkaline: The first element in each period is usually an alkaline metal (group 1).
- Noble: Each period ends with a noble gas (group 18).
- Metallic: The elements on the left of the period have metallic properties.
- Nonmetallic: Elements on the right side of the period have nonmetallic properties.
- Noble: Noble gases are a type of nonmetal, with complete outer electron shells.
- Representative: Noble gases are part of the representative elements because they have a predictable, stable electron configuration.
The periodic table is structured to show periodic trends in properties, such as atomic size, ionization energy, and electronegativity. Moving across periods, elements show a gradual change in these properties, reflecting the increasing number of protons and electrons, which affects how atoms interact with each other. Groups contain elements with similar behaviors because they have the same number of electrons in their outermost shells, which largely determine their chemical reactivity.