To What Family of the Periodic Table Would Element X Be Most Likely to Belong? Explain?

Chapter two. Atoms, Molecules, and Ions

ii.v The Periodic Table

Learning Objectives

By the end of this section, you will exist able to:

• State the periodic law and explicate the organisation of elements in the periodic table
• Predict the general backdrop of elements based on their location within the periodic table
• Identify metals, nonmetals, and metalloids past their properties and/or location on the periodic tabular array

As early chemists worked to purify ores and discovered more elements, they realized that diverse elements could be grouped together by their like chemical behaviors. One such grouping includes lithium (Li), sodium (Na), and potassium (Chiliad): These elements all are shiny, deport rut and electricity well, and take similar chemical properties. A second grouping includes calcium (Ca), strontium (Sr), and barium (Ba), which likewise are shiny, practiced conductors of heat and electricity, and take chemic properties in mutual. However, the specific properties of these 2 groupings are notably different from each other. For example: Li, Na, and K are much more reactive than are Ca, Sr, and Ba; Li, Na, and Grand form compounds with oxygen in a ratio of two of their atoms to one oxygen atom, whereas Ca, Sr, and Ba form compounds with i of their atoms to one oxygen atom. Fluorine (F), chlorine (Cl), bromine (Br), and iodine (I) also exhibit similar properties to each other, but these backdrop are drastically different from those of any of the elements above.

Dimitri Mendeleev in Russian federation (1869) and Lothar Meyer in Germany (1870) independently recognized that there was a periodic relationship amid the properties of the elements known at that time. Both published tables with the elements arranged according to increasing atomic mass. Merely Mendeleev went one step further than Meyer: He used his table to predict the existence of elements that would accept the properties similar to aluminum and silicon, but were all the same unknown. The discoveries of gallium (1875) and germanium (1886) provided great support for Mendeleev's work. Although Mendeleev and Meyer had a long dispute over priority, Mendeleev's contributions to the development of the periodic table are now more widely recognized (Figure 1).

Figure i. (a) Dimitri Mendeleev is widely credited with creating (b) the outset periodic table of the elements. (credit a: modification of work by Serge Lachinov; credit b: modification of work by "Den fjättrade ankan"/Wikimedia Eatables)

By the twentieth century, information technology became apparent that the periodic relationship involved atomic numbers rather than atomic masses. The modern statement of this relationship, the periodic police, is as follows: the properties of the elements are periodic functions of their diminutive numbers. A modern periodic table arranges the elements in increasing order of their atomic numbers and groups atoms with similar properties in the same vertical cavalcade (Figure ii). Each box represents an element and contains its atomic number, symbol, average diminutive mass, and (sometimes) proper noun. The elements are arranged in vii horizontal rows, chosen periods or series, and 18 vertical columns, called groups. Groups are labeled at the top of each column. In the United states, the labels traditionally were numerals with capital letters. Nevertheless, IUPAC recommends that the numbers 1 through 18 be used, and these labels are more common. For the tabular array to fit on a single page, parts of two of the rows, a total of 14 columns, are ordinarily written below the main trunk of the tabular array.

Effigy 2. Elements in the periodic table are organized according to their properties.

Many elements differ dramatically in their chemic and concrete backdrop, but some elements are similar in their behaviors. For example, many elements appear shiny, are malleable (able to be deformed without breaking) and ductile (tin be drawn into wires), and conduct heat and electricity well. Other elements are not shiny, malleable, or ductile, and are poor conductors of rut and electricity. We tin sort the elements into large classes with common properties: metals (elements that are shiny, malleable, proficient conductors of heat and electricity—shaded yellow); nonmetals (elements that appear tedious, poor conductors of oestrus and electricity—shaded light-green); and metalloids (elements that conduct estrus and electricity moderately well, and possess some backdrop of metals and some backdrop of nonmetals—shaded purple).

The elements can also be classified into the main-group elements (or representative elements) in the columns labeled ane, 2, and 13–18; the transition metals in the columns labeled 3–12; and inner transition metals in the two rows at the bottom of the table (the top-row elements are called lanthanides and the bottom-row elements are actinides; Figure three). The elements can exist subdivided further by more specific properties, such equally the composition of the compounds they course. For case, the elements in group 1 (the first column) class compounds that consist of one atom of the element and ane atom of hydrogen. These elements (except hydrogen) are known as alkali metals, and they all accept like chemic backdrop. The elements in group 2 (the second column) form compounds consisting of 1 atom of the chemical element and two atoms of hydrogen: These are called alkaline metal earth metals, with similar properties among members of that grouping. Other groups with specific names are the pnictogens (group 15), chalcogens (group xvi), halogens (group 17), and the noble gases (grouping 18, also known equally inert gases). The groups tin as well be referred to past the first element of the grouping: For example, the chalcogens can be chosen the oxygen group or oxygen family. Hydrogen is a unique, nonmetallic element with backdrop similar to both group 1A and group 7A elements. For that reason, hydrogen may be shown at the summit of both groups, or past itself.

Figure 3. The periodic table organizes elements with similar properties into groups.

Click on this link for an interactive periodic table, which you can use to explore the properties of the elements (includes podcasts and videos of each element). You may likewise want to effort this ane that shows photos of all the elements.

Example 1

Naming Groups of Elements
Atoms of each of the following elements are essential for life. Requite the group name for the following elements:

(a) chlorine

(b) calcium

(c) sodium

(d) sulfur

Solution
The family names are as follows:

(a) element of group vii

(b) alkaline earth metallic

(c) alkali metal

(d) chalcogen

Check Your Learning
Requite the group name for each of the post-obit elements:

(a) krypton

(b) selenium

(c) barium

(d) lithium

Answer:

(a) noble gas; (b) chalcogen; (c) alkaline globe metallic; (d) alkaline metal

In studying the periodic tabular array, you might have noticed something almost the atomic masses of some of the elements. Element 43 (technetium), chemical element 61 (promethium), and most of the elements with atomic number 84 (polonium) and college accept their atomic mass given in square brackets. This is washed for elements that consist entirely of unstable, radioactive isotopes (you volition acquire more about radioactivity in the nuclear chemical science affiliate). An average atomic weight cannot be determined for these elements considering their radioisotopes may vary significantly in relative abundance, depending on the source, or may not even exist in nature. The number in square brackets is the diminutive mass number (and approximate atomic mass) of the most stable isotope of that element.

Central Concepts and Summary

The discovery of the periodic recurrence of similar properties among the elements led to the formulation of the periodic table, in which the elements are arranged in lodge of increasing atomic number in rows known equally periods and columns known as groups. Elements in the same group of the periodic tabular array take similar chemical backdrop. Elements can be classified as metals, metalloids, and nonmetals, or as a main-group elements, transition metals, and inner transition metals. Groups are numbered 1–eighteen from left to right. The elements in grouping ane are known every bit the alkali metals; those in group 2 are the alkaline earth metals; those in 15 are the pnictogens; those in 16 are the chalcogens; those in 17 are the halogens; and those in 18 are the noble gases.

Chemistry Stop of Chapter Exercises

1. Using the periodic table, classify each of the following elements every bit a metal or a nonmetal, then farther classify each as a main-group (representative) element, transition element, or inner transition metallic:

   (a) uranium

   (b) bromine

   (c) strontium

   (d) neon

   (e) gold

   (f) americium

   (thousand) rhodium

   (h) sulfur

   (i) carbon

   (j) potassium

2. Using the periodic table, allocate each of the following elements every bit a metal or a nonmetal, and so further allocate each as a principal-grouping (representative) element, transition element, or inner transition element:

   (a) cobalt

   (b) europium

   (c) iodine

   (d) indium

   (e) lithium

   (f) oxygen

   (h) cadmium

   (i) terbium

   (j) rhenium

3. Using the periodic table, identify the lightest fellow member of each of the post-obit groups:

   (a) noble gases

   (b) alkaline globe metals

   (c) alkali metals

   (d) chalcogens

4. Using the periodic table, identify the heaviest member of each of the following groups:

   (a) alkali metals

   (b) chalcogens

   (c) noble gases

   (d) alkaline globe metals

5. Utilise the periodic tabular array to give the proper noun and symbol for each of the post-obit elements:

   (a) the element of group 0 in the same period as germanium

   (b) the alkaline globe metal in the same period equally selenium

   (c) the element of group vii in the same menstruum as lithium

   (d) the chalcogen in the same menstruum as cadmium

6. Employ the periodic table to give the name and symbol for each of the following elements:>

   (a) the halogen in the same period equally the alkali metallic with 11 protons

   (b) the element of group ii in the same period with the neutral noble gas with 18 electrons

   (c) the noble gas in the same row as an isotope with 30 neutrons and 25 protons

   (d) the noble gas in the aforementioned period as gold

7. Write a symbol for each of the following neutral isotopes. Include the atomic number and mass number for each.

   (a) the alkali metal with xi protons and a mass number of 23

   (b) the noble gas element with 75 neutrons in its nucleus and 54 electrons in the neutral atom

   (c) the isotope with 33 protons and 40 neutrons in its nucleus

   (d) the element of group ii with 88 electrons and 138 neutrons

8. Write a symbol for each of the following neutral isotopes. Include the diminutive number and mass number for each.

   (a) the chalcogen with a mass number of 125

   (b) the halogen whose longest-lived isotope is radioactive

   (c) the noble gas, used in lighting, with 10 electrons and 10 neutrons

   (d) the lightest alkali metal with three neutrons

Glossary

actinide

inner transition metal in the bottom of the lesser two rows of the periodic table

element of group i

element in group i

alkali metal earth metal

element in group two

chalcogen

chemical element in group 16

group

vertical column of the periodic table

halogen

element in grouping 17

inert gas

(also, element of group 0) chemical element in grouping 18

inner transition metal

(also, lanthanide or actinide) element in the bottom two rows; if in the commencement row, also called lanthanide, or if in the second row, besides called actinide

lanthanide

inner transition metal in the acme of the bottom two rows of the periodic table

main-group chemical element

(besides, representative element) chemical element in columns 1, ii, and 12–eighteen

metallic

element that is shiny, malleable, expert conductor of heat and electricity

metalloid

chemical element that conducts oestrus and electricity moderately well, and possesses some backdrop of metals and some backdrop of nonmetals

element of group 0

(also, inert gas) element in group eighteen

nonmetal

element that appears dull, poor usher of estrus and electricity

flow

(also, series) horizontal row of the periodic tabular array

periodic constabulary

properties of the elements are periodic function of their atomic numbers.

periodic tabular array

table of the elements that places elements with similar chemical properties close together

pnictogen

element in group 15

representative element

(as well, chief-group element) chemical element in columns one, 2, and 12–eighteen

series

(also, flow) horizontal row of the period table

transition metal

element in columns 3–xi

Solutions

Answers to Chemistry End of Chapter Exercises

1. (a) metallic, inner transition metal; (b) nonmetal, representative element; (c) metal, representative element; (d) nonmetal, representative element; (e) metal, transition metal; (f) metallic, inner transition element; (g) metallic, transition metal; (h) nonmetal, representative chemical element; (i) nonmetal, representative chemical element; (j) metallic, representative chemical element

3. (a) He; (b) Be; (c) Li; (d) O

5. (a) krypton, Kr; (b) calcium, Ca; (c) fluorine, F; (d) tellurium, Te

vii. (a) [latex]_{eleven}^{23}\text{Na}[/latex]; (b) [latex]_{54}^{129}\text{Xe}[/latex]; (c) [latex]_{33}^{73}\text{As}[/latex] ; (d) [latex]_{88}^{226}\text{Ra}[/latex];

harperency1954.blogspot.com

Source: https://opentextbc.ca/chemistry/chapter/2-5-the-periodic-table/

Share this post