Chemistry 6.1-6.3

Compare the size of ions to the size of the atoms from which they form.

-cations are always smaller than the atoms from which the form. -anions are always larger than the atoms from which they form.

Into what four classes can elements be sorted based on their electron configurations?

elements can be sorted into noble gases, representative elements, transition metals, or inner transition metals based on their electron configurations

In general, how can the periodic trends displayed by elements be explained?

The trends that exist among these properties can be explained by variations in atomic structure

Which of these elements are transition metals: Cu, Sr, Cd, Au, Al, Ge, Co?

Au

How do electronegativity values vary within groups and across periods?

Electronegativity values decrease from top to bottom within a group. -representative elements, values tend to increase from left to right across a period.

What types of information can be included in a periodic table?

symbols, names of the elements, and information about the structure of the atoms.

How many electrons are in the highest occupied energy level of an element in Group 5A?

5

Why do the elements potassium and sodium have similar chemical properties?

Both elements, sodium (Na) and potassium (K) lie in the Group 1 column of the Periodic Table, which contains the members of the Alkali Metals family. Members within a family, or column, of elements tend to have similar chemical properties.

How did chemists begin the process of organizing elements?

Chemists used the properties of elements to sort them into groups

How do first ionization energies vary within groups and across periods?

First ionization energy tends to decrease from top to bottom within a group and increase from left to right across a period

How are elements arranged in the modern periodic table?

In the modern periodic table, elements are arranged in order of increasing atomic number

What property did Mendeleev use to organize his periodic table?

Mendeleev arranged the elements in his periodic table in order of increasing atomic mass

Name two elements that have properties similar to those of the element sodium.

Sodium and potassium have similar properties because they have similar electron configurations.

Arrange these elements in order of decreasing atomic size: sulfur, chlorine, aluminum, and sodium. Does your arrangement demonstrate a periodic trend or a group trend?

Sodium, Aluminum, Sulfur, Chlorine

When do ions form?

Some atoms are more stable when they gain or lose an electron (or possibly two) and form ions. This results in a full outermost electron shell and makes them energetically more stable. Now, because the number of electrons does not equal the number of protons, each ion has a net charge.

Identify each element as a metal, a metalloid, or a nonmetal. a. gold b. silicon c. sulfur d. barium

a. Metal b. Nonmetal c. Nonmetal d. Metal

Based on the following electron configurations, identify each element as a representative element, transition metal, or noble gas. a. 1s22s22p63s23p63d104s24p6 b. 1s22s22p63s23p63d64s2 c. 1s22s22p63s23p2

a. This is a noble gas. It has a np6 configuration, and 8 electrons (4s2, 4p6) in its outer shell. This is krypton. b. transition element. This is iron. c. silicon. representative element or metalloid

How does atomic size change within groups and across periods?

atomic size increases from top to bottom within a group and decreases from left to right across a period

Which of the following sets of elements have similar physical and chemical properties? a. oxygen, nitrogen, carbon, boron b. strontium, magnesium, calcium, beryllium c. nitrogen, neon, nickel, niobium

b. strontium, magnesium, calcium, beryllium

Name the three broad classes of elements.

three classes of elements are metals, nonmetals, and metalloids