Periodic Properties of Metals

What group elements are being studied for flame spectra and chemical reactions?

• group 1A - Alkali metals

• group 2A - Alkaline earth metals

What elements were worked with in the lab?

Lithium, sodium, potassium, magnesium, calcium, strontium, and barium.

When heated metal ions form:

Atoms —> electrons in the atoms absorb heat and jump to higher energy-orbitals.

The color observed in a flame corresponds to:

the energy difference between electron orbitals.

where does the color in the flame come from?

cation

What compound does not produce a characteristic color?

Magnesium

• the energy required for the transition is too great

What elements are being studied for chemical reactions in the second part of the experiment?

• Alkaline earth metals:

  • chloride salts of calcium, magnesium, strontium, and barium

In the second part of the experiment what were group 2 metals mixed with?

• Sulfates (H₂SO₄)

• Carbonates (Na₂CO₃)

Insoluble =

White precipitate

Soluble =

Clear

What solubility trends do you notice as you go down the group IIA sulfates and IIA carbonates?

• sulfates - solubility decreases

• carbonates - are all insoluble (solubility may decrease)

Carbonate salts can be identified by:

Bubbling when acid is added to a solution.

Chloride salts of what group 2 metals were tested?

• MgCl₂

• CaCl₂

• SrCl₂

• BaCl₂