Atomic and physical properties table of group 2 elements
Answers
Explanation:
1. low melting point
2. low boiling point
3. shiny
4.lose their outermost electron to form actions
5. low densities
Explanation:
ncluded in the group two elements are Beryllium(Be), Magnesium(Mg), Calcium(Ca), Strontium(Sr), and Barium(Ba). Usually, there is no need to store these elements in oil, unlike the group one elements. For a metal, alkali earth metals tend to have low melting points and low densities. Being a metal, they are obviously good conductors of heat and electricity.
The general electronic configuration of Group 2 elements is ns2. Alkali earth metals have the capability to lose the two electrons in their outer shell. Thus, they react with other elements and form ionic compounds. Let’s take some examples to understand the reactions of such metals.
The reaction of magnesium with water takes place very slowly, wherein, the release of hydrogen gas is also very slow. However, upon reaction, calcium tends to frizz away quite quickly. As a result, an alkaline solution is formed, which can be understood better by the following equation:
calcium + water → calcium hydroxide + hydrogen i.e.
Ca (s) + 2 H2O (l) → Ca (OH)2 (aq) + H2 (g)
Strontium tends to give off the hydrogen gas, much more easily.
Barium also reacts very quickly with water.
Since the reactive ability of group two elements is quite less in comparison to group one elements, they are used to be added in acids, in order to dilute them. For example, magnesium and calcium, added in hydrochloric acid would produce the following output:
magnesium + hydrochloric acid → magnesium chloride + hydrogen
Mg (s) + 2 HCl (aq) → MgCl2 (aq) + H2 (g)
Uses of the Alkali Earth Metals
As far as the uses of the group two elements and their compounds are concerned, there is a lot to be understood on that front.
Magnesium usually burns with a bright whitish flame and this has allowed it to be used in fireworks and rescue flares, along with the other type of such variety. A unique use of the metal is in the manufacture and production of high-performance car engines.
Let us take, for example, the Volkswagen ‘Beetle’ has a magnesium crankcase and other engine parts. The Porsche 911 contains more than 50 kilogram of magnesium. It is brought into use because of its low density, thereby reducing fuel consumption and reducing the emitting of pollution from these cars. Magnesium compounds are useful as well. For example:
The active ingredient Magnesium hydroxide is used some indigestion remedies. It neutralizes the excess acid that causes heartburn in humans.
Magnesium oxide has a very high melting point hence used as a lining inside furnaces.
Epsom salt, which is a laxative, has Magnesium sulphate in it.
Strontium compounds find their use in fireworks to produce a crimson red colour. Barium compounds are very poisonous. Rat poison has barium carbonate in it. However, you might have heard of ‘barium meals’ in hospitals. Patients swallow a white substance that shows up their digestive tract when X-rayed. This contains barium sulphate, which is insoluble in water and so just passes through your body without doing any harm.