Rucete ✏ Chemistry In a Nutshell
Alkaline Earth Metals - Group 2A : ns^2 , n ≥ 2
1 Atom : Be (4) Mg (12) Ca (20) Sr (38) Ba (56) Ra (88)
2 Less reactive than Group 1A metals
3 Tendency to form M2+, Ions 2+
The lower move in same column, the greater tendency.
4 React of water
week reaction
1. Mg : weak reaction when heated
2 Ca, Sr, Ba : reaction with water
5 Combination with oxygen
The lower move in same column, the greater reactivity.
--> Be and Mg only react with high temperature and from BeO, MgO
6 Generation and reaction by salt and water
MgO(s) + 2HCl(aq) → MgCl2(aq) + H2o(l)
7 Physical characteristics : Alkali earth metals are generally silvery, soft and low dense. Combine with halogen elements to produce salts. They do not react violently with water like alkali metals, but combine to produce strong base hydroxide.
It exists in relatively large quantities except beryllium and radium, which are radioactive elements. Magnesium and calcium, in particular, are included in the eight elements that make up the crust, and are widely distributed within living organisms. Alkali metals are silver or gray metals that gradually rust in the air and lose metal luster. Both melting and boiling points are higher than alkali metals.
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Chemistry in a nutshell