CHEM 01LA Lecture Notes - Lecture 4: Alkaline Earth Metal, Electronegativity, Atomic Radius
CHEM 01LA Experiment 4: The Alkaline Earths and Halogens
●Experimental Purpose:
○The purpose of this experiment is to determine the solubility trends of the alkaline
earth group, as well as the relative oxidizing strengths of several halogens
●Alkaline Earth Metals (Group II A)
○Consists of barium, beryllium, calcium, magnesium, radium, and strontium
○Highly electropositive, the second most reactive group of metals
Alkali Metals (Group I A)
Alkaline Earth Metals (Group II A)
●More reactive
●Very soluble in water
●Larger nuclear charge
●Smaller atomic radius
●Higher melting/ boiling points
●Higher densities
●Harder
○The solubility of alkaline earth sulfates decreases
with increasing
cation size
○Note: all of the alkaline earth metals exist in their compounds and in solution as
M2+ cations
●Halogens (Group VII A)
○Halogen = “salt former”
Alkaline Earth Metals (Group II A)
Halogens (Group VII A)
●Exist as monotomic molecules
●Lose electrons to form cations
●Occur extensively in nature
●Exist as diatomic molecules
●Gain electrons to form anions
●Oxidizing agents
●General Terminology
○Cation: a positive ion
■Example: Mg2+
Document Summary
Chem 01la experiment 4: the alkaline earths and halogens. The purpose of this experiment is to determine the solubility trends of the alkaline earth group, as well as the relative oxidizing strengths of several halogens. Consists of barium, beryllium, calcium, magnesium, radium, and strontium. Highly electropositive, the second most reactive group of metals. The solubility of alkaline earth sulfates decreases with increasing cation size. Note : all of the alkaline earth metals exist in their compounds and in solution as. Halogen : an element in group 17 in the periodic table (diatomic molecules) Halide : the negative ion ( anion ) formed by addition of an electron to a halogen. Oxidation : loss of electrons (algebraic increase in charge) Reduction : gain of electrons (algebraic decrease in charge) Oxidizing agent : causes oxidation by removing electrons from other species. The strongest oxidizing agent is the most easily reduced. Reducing agent : causes reduction by giving electrons to other species.
