Question

2 low ionization energy is a characteristic of a
3 what does atomic radius measure?
4 describe the change in the atomic size across a period and down a group.
5 which element has the largest atomic radius?
6 explain the main difference between metals and nonmetals.

Explanation:

• Question 2: Ionization energy is the energy required to remove an electron from an atom. A low ionization energy means it is relatively easy to remove an electron, which is a characteristic of metals. Metals tend to lose electrons to form positive ions.
• Question 3: Atomic radius is the distance from the nucleus of an atom to its outermost electron shell.
• Question 4:
• Across a period: As we move from left to right across a period in the periodic table, the atomic size decreases. This is because the number of protons in the nucleus increases (increasing the positive charge), and electrons are added to the same energy level. The increased nuclear charge pulls the electrons closer to the nucleus.
• Down a group: As we move down a group, the atomic size increases. This is because new electron shells are added. Each new shell is farther from the nucleus, so the outermost electrons are more shielded from the nuclear charge by the inner - shell electrons.
• Question 5: Generally, elements on the left - hand side of the periodic table (metals) have larger atomic radii. For example, in the alkali metals (Group 1), cesium (Cs) has a very large atomic radius compared to many other elements.
• Question 6:
• Metals: Tend to lose electrons (form positive ions). They have low ionization energies (easily lose electrons), are good conductors of heat and electricity (due to the delocalization of electrons), and are malleable and ductile (the metallic bonding allows layers of atoms to slide over each other).
• Non - metals: Tend to gain electrons (form negative ions) or share electrons (in covalent bonds). They have relatively high ionization energies (harder to lose electrons), and are usually poor conductors of heat and electricity (except for some like graphite, which is a form of carbon).

Answer:

• 2: Low ionization energy is a characteristic of a metal.
• 3: Atomic radius is the distance from the nucleus of an atom to its outermost electron shell.
• 4: Across a period, atomic size decreases; down a group, atomic size increases.
• 5: Generally, metals (e.g., alkali metals like Cs) have large atomic radii.
• 6: Metals lose electrons (form positive ions), have low ionization energies, and are good conductors; non - metals gain or share electrons, have relatively high ionization energies, and are usually poor conductors.