Chemistry, Ch. 5

What did Henry Moseley do?

What did Henry Moseley do?

Found the atomic charge or atomic number

What is periodic law?

The physical and chemical properties of the elements are periodic functions of their atomic numbers

What is chemistry?

The study of the composition, structure, and properties of matter and the changes it undergoes

What is the name for the s block?

Reactive metals

What is the name for the f block?

Rare earth metals

What is the name for the s and p blocks?

Main group elements

What are five properties of alkali metals?

Highly reactive, soft enough to be cut with a butter knife, lowest electronegativity, good conductors of heat and electricity

What are fivve properties of alkaline earth metals?

Harder than group 1 elements, but still softer than the transition metals, reactive, malleable, luster, good conductors of heat and electricity

What are five properties of transition metals?

Good conductors of heat and electivity, ductile, malleable, luster, high melting points, low reactivity

What are five properties of lanthanides?

luster, reactive, malleable, ductile, good conductors of heat and electrivity

What are five properties of actinides?

radioactive, reactive, malleable, ductile, good conductors

What are five properties of the hallogens?

highly reactive, brittle, good insulators of heat and electicity, dull

What is a property of metalloids?

Semiconductors

What is the group and period of the metal that is a liquid?

Group 12, period 6

What is the group and period of the non-metal that is a liquid?

Group 17, period 4

Define atomic radii

One-half the distance between the nuclei of two identical atoms bonded together

What is the tren dof atomic radii left to right?

Decreases

What is the atomic radii trend top to bottom?

Increases

Why does the atomic radii have that left to right trend?

The electrons are only being added to the same energy level and there are more protons to create a stronger force pulling the electrons to the nucleus.

What is ionization energy?

The amount of energy necessary to remove one electron from an atom

What is the ionization energy trend left to right?

increases

What is the ioinization energy trend top to bottom?

decreases

Why does ionization energy have that trend?

The same reasons as atomic radii but reversed

What is the units for ionization energy?

kJ/mol

What is electron affinity?

The energy change that occurs when an electron is acquired by a neutral atom

What is the left to right electron affinity trend?

More negative

What is the top to bottom electron affinity trend?

Less negative

Why are these the electron affinity trends?

The electrons are farther away from the nucleus the larger the radii get and radii are smallest in the top right of the periodic table

What is ionic radii?

One-half the distance between the nuclei of two identical ions bonded together

What is the left to right trend for ionic radii?

Decrease with a large jump at the break from cations to anions

Are cations radii bigger or smaller?

Smaller

Are anions radii bigger or smaller?

Bigger

What type of element forms cations?

Metals

What type of element forms anions?

Non-metals

What are valence electrons?

The electrons with the highest enters level of an atom that are available to be lost, gained, or shared in the formation of chemical compounds

What is electronegativity?

THe measure of the ability of an atom in a chemical compound to attract electrons

What is the left to right trend for electronegativity?

Increases

What is the top to bottom trend for electronegativity?

Decreases

Why are these the trends for electronegativity?

Electrons are farther away from the nucleus with smaller radii so there is not as strong of an attraction for the electrons

What is the value of fluorine for electronegativity?

4

What is the atomic mass standard?

1/12 the mass of a C-12 atom

What is a semiconductor?

Elements which has electrons that are more tightly bound to their nucleus and therefore have intermediate conductive properties