Physical and Chemical Properties of Metals

All three items add color How are their properties different from One Another?

Properties of a Substance Physical Property: can be observed or measured. Influenced by the molecular structure of atoms Examples: color, size, shape, length, density, boiling point, solubility

Properties of a Substance Chemical Property: Describe the ability to react or combine with another substance to produce a new product Influenced by how the elements bond with other elements. Examples: Reactivity, Flammability, Sour or Bitter taste, Corrosive, Tarnishes in presence of oxygen, rusts

Metals

Molecular structure in metals Crystalline structure: 3- dimensional, repeating arrangement of atoms. Reflects light easily, giving metals their luster (shine)

Molecular structure in metals Creates strong structure giving metals other properties: Hardness High melting and boiling points

Metallic Bond: How metals Bond Together Normal bond – electrons are in fixed location Metallic bond – free electrons moving around each nuclei in the crystal. Creates close bond

Metallic Bond: How metals Bond Together Properties: Most have high density Density: amount of mass per unit volume Most are high density– atoms are closely packed together

Metallic Bond: How metals Bond Together Properties: Malleable – flattened or stretched without breaking

Metallic Bond: How metals Bond Together Properties: Ductile – ability to be pulled into a wire without breaking

Metallic Bond: How metals Bond Together Properties: Thermal conductivity – ability for heat to pass through Electrical conductivity – ability for an electrical charge to pass through

Chemical Properties of Metals The octet rule is a chemical rule of thumb that says atoms of main-group elements tend to combine in such a way that each atom has eight electrons in its valence shell, giving it the same electronic configuration as a noble or inert gases. Valence shell is outermost shell. “8” becomes magic number in determining if outermost electron cloud is full Smaller elements are full with “2”

Chemical Properties of Metals Metals tend to have 1, 2, or 3 valence electrons

Chemical Properties of Metals Less energy to “lose” electrons in outer cloud than gain enough to get to magic number of “8” Once the electrons are lost, the cloud goes away. New outermost cloud that has magic number of “8”

No rule for transition metals, usually 1 or 2 valence electrons

Chemical Properties of Metals Fewer electrons to lose – More reactive Group 1 – Alkali Metals: 1 electron in outermost level, so very reactive Group 2 – lose 2 Group 3- 12: usually lose 1 or 2, some exceptions Metals in Groups 13 – 16: lose or gain 3 or 4 electrons.

Chemical Properties of Metals Corrosive (react with acid) Tarnish or Rusting – react with oxygen Some react explosively with water

Group 1 – Alkali Metals Physical Properties Chemical Properties Low melting points Low densities (lower than other metals) Silver in color Malleable Softer than most other metals Ductile Good conductors of heat and electricity Most reactive metal React easily with halogens Lose one electron to react Explode when exposed to water Tarnish easily

Group 2 – Alkaline Earth Metals Physical Properties Chemical Properties Lose 2 electrons when reacting React easily with the halogens and water High boiling and melting points Low density Silver in color Ductile and Malleable Softer than most other metals (except the alkali metals)

Groups 3 – 12 Transition Metals Physical Properties Chemical Properties Valence electrons are found in more than one shell No set rule for number of valence electrons Form complex ions Ductile and Malleable Good conductors of heat and electricity High strength levels High density High melting and boiling points Form solids at room temperature (except mercury) Silvery blue in color (at room temperature)

Other metals: Found in Groups 13 – 16 Properties Physical Properties: Ductile and Malleable High density Chemial Properties Lose or gain 3 or 4 electrons

Lanthanides and Actinides Properties Physical Properties: Many are manmade Chemial Properties Unstable Nucleus - Radioactivity