Periodic Table of Alkali, Alkaline Earth, Noble Gases, Halogens, and Transition Metals

What is the arrangement of the periodic table based on?

Atomic numbers, which represent the number of protons in the nucleus.

What is the electron configuration of alkali metals in Group I?

They have one electron in their outer shell, specifically in an s orbital.

Why is hydrogen placed above alkali metals in the periodic table?

Hydrogen has similar properties due to its one proton and one electron arrangement.

What happens when alkali metals react with water?

They react rapidly to produce hydrogen gas and can ignite due to heat.

What are alkaline earth metals and where are they found in the periodic table?

They are found in Group 2 and have two electrons in their outer shell.

Why are alkaline earth metals less reactive than alkali metals?

They require more energy to remove two electrons compared to one.

What is a common use of magnesium?

It is used in flares and fireworks due to its bright burning properties.

What distinguishes noble gases in Group 18?

They are chemically inert and have full outer electron shells.

What is the electron configuration of helium?

Helium has a full outer shell of two s electrons.

Which noble gases have been found to form compounds?

Compounds have been formed with radon, xenon, krypton, and argon.

What is the general electron configuration of halogens?

They have the configuration ns2np5, giving them seven valence electrons.

What does the term 'halogen' mean?

It means 'salt-former' because halogens readily react with alkali and alkaline earth metals.

What are the physical states of chlorine, bromine, and iodine at room temperature?

Chlorine and fluorine are gases, bromine is a liquid, and iodine is a solid.

Why are halogens not found free in nature?

Due to their high reactivity, they readily form compounds.

What is the outer shell electron structure of beryllium?

Beryllium has two electrons in its outer shell (1s2 2s2).

What is a characteristic property of radium?

Radium is radioactive and is categorized as a radioisotope.

What is a use of calcium compounds?

Calcium compounds are used in cement and as deicers.

What is the reactivity trend of alkali metals compared to alkaline earth metals?

Alkali metals are more reactive than alkaline earth metals.

What happens to the reactivity of alkali metals as you move down the group?

Reactivity increases as you move down the group.

What is the atomic number of cesium?

Cesium has an atomic number of 55.

How do noble gases glow when an electric current is passed through them?

They emit light due to the excitation of their electrons.

What is the atomic number of barium?

Barium has an atomic number of 56.

What is the significance of the outer shell electron configuration for noble gases?

It makes them stable and resistant to chemical reactions.

What is the atomic number of radium?

Radium has an atomic number of 88.

Why is fluorine not shown in certain illustrations?

Fluorine is too corrosive and will destroy the glass container.

Where is chlorine commonly found?

Chlorine is found in table salt, the oceans (about 2% chloride ion by weight), and lakes like the Great Salt Lake.

What is the electron configuration of halogens?

The electron configuration in the outer shell is ns2np5.

How does the reactivity of halogens change with atomic number?

As the atomic number increases, the reactivity of the halogens decreases.

What states of matter do fluorine, chlorine, bromine, and iodine exist in at room temperature?

Fluorine and chlorine are gases, bromine is a liquid, and iodine is a solid.

What are transition elements?

Transition elements are found in Groups 3-12 on the periodic table and are characterized by having unfilled d sublevels.

What is the electron configuration of scandium, the first transition element?

[Ar] 3d1 4s2.

What are the typical properties of transition metals?

They display typical metallic properties and are less reactive than metals in Groups 1 and 2.

What is a unique characteristic of many transition element compounds?

Many transition element compounds are brightly colored due to inner-level d electron transitions.

What are lanthanides and actinides?

They are elements with unfilled f orbitals, with lanthanides being metals similar to Group 2 elements and actinides being radioactive.

What is the general electron configuration for elements in the f block?

(n - 2)f1-14ns2.

What are some uses of lanthanides?

Lanthanides are used in alloys for strength, petroleum refining, and optical devices like night vision goggles.

What are the primary applications of actinides?

Actinides are used as energy sources in devices like cardiac pacemakers and in nuclear power plants.

How is atomic radius defined?

Atomic radius is defined as one-half the distance between the nuclei of two identical atoms bonded together.

What is the periodic trend for atomic radius across a period?

The atomic radius generally decreases from left to right across a period.

What is the group trend for atomic radius?

The atomic radius generally increases from top to bottom within a group.

What causes the atomic radius to decrease across a period?

Increased positive charge from protons pulls electrons closer to the nucleus.

What causes the atomic radius to increase down a group?

An increase in the number of occupied principal energy levels outweighs the increase in nuclear charge.