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Scottish chemist Thomas Charles Hope (1766 - 1844).

Barium

Barium minerals were known by alchemists in the early Middle Ages. Stones of the mineral barite found in Bologna, Italy (also known as Bologna stones ), were known to glow after exposure to light. Carl Scheele ( [link] ) identified barite in 1774, but did not isolate barium. Barium was first isolated as Ba 2+ in solution by Sir Humphry Davy ( [link] ) in 1808. The oxidized barium was at first called barote , by Guyton de Morveau, ( [link] ) which was changed by Antoine Lavoisier ( [link] ) to baryta , from which barium was derived to describe the metal.

German-Swedish pharmaceutical chemist Carl Wilhelm Scheele (1742 - 1786). Author Isaac Asimov has called him "hard-luck Scheele" because he made a number of chemical discoveries before others who are generally given the credit.
French chemist and politician Louis-Bernard Guyton de Morveau (1737 - 1816) changed his name to Guyton-Morveau after the French Revolution.
French chemist and biologist Antoine-Laurent de Lavoisier (1743 – 1794).

Radium

Radium was discovered by Marie Curie ( [link] ) and her husband Pierre ( [link] ) in 1898 while studying pitchblende. After removing uranium they found that the remaining material was still radioactive. They then separated out a radioactive mixture consisting mostly of barium and an element that gave crimson spectral lines that had never been documented before. In 1910, radium was isolated as a pure metal by Curie and André-Louis Debierne ( [link] ) through the electrolysis of a radium chloride solution by using a mercury cathode and distilling in an atmosphere of hydrogen gas.

Marie Curie (1867-1934). Copyright Academy of Achievement.
French physicist Pierre Curie (1859 – 1906).
French chemist André-Louis Debierne (1874 - 1949).

Abundance

The abundance of the alkaline earth elements is given in [link] . Beryllium is rare, but found in the mineral beryl (Be 3 Al 2 Si 6 O 18 ). While magnesium is widespread within the Earth's crust, commercial sources tend to be from sea water as well as the carbonate minerals magnesite (MgCO 3 ) and dolomite [(Ca,Mg)CO 3 ]. Calcium is also commonly found as the carbonate, however, strontium and barium are present as the sulphates celestine (SrSO 4 ) and barites (BaSO 4 ), respectively.

Abundance of alkaline earth elements.
Element Terrestrial abundance (ppm)
Be 2.6 (Earth’s crust), 6 (soil), 2 x 10 -7 (sea water)
Mg 23,000 (Earth’s crust), 10,000 (soil), 1,200 (sea water)
Ca 41,000 (Earth’s crust), 20,000 (soil), 400 (sea water)
Sr 370 (Earth’s crust), 200 (soil), 8 (sea water)
Ba 500 (Earth’s crust), 500 (soil), 0.001 (sea water)
Ra 6 x 10 -7 (Earth’s crust), 8 x 10 -7 (soil), 1 x 10 -10 (sea water)

Calcium is a key element for living. Not only is it present as the skeletal material for shell fish and crabs (CaCO 3 ) its phosphate derivative, hydroxyapetite [Ca 5 (OH)(PO 4 ) 3 ] is the structural material of bones and teeth. Calcium is also present in soft tissue at a level of ca. 22g/kg. Calcium is a vital metal for the following:

  • Links large molecules together.
  • Used in the activation of muscles
  • Used in enzyme activation by stabilization of particular conformations of proteins to be acted upon by enzymes.

Questions & Answers

why should a firm close down when it's unable to pay it's variable cost?
ANDREW Reply
what is oligopolistic competitive market?
ngong
exchange of goods and services between countries is call
Hosea Reply
foreign trade
Peace
what is constant opportunity cost
Tiffany Reply
Constant opportunity cost means the value of sacrifice remains constant in every step.
Dipam
Gross Domestic Product GDP
Yusuf Reply
what is g d p
Jayapal Reply
gross daily performance
domingo
How best can a poor country respond to an economic crisis , what does it have to sacrifice.
Bah Reply
they should pay tax as progressive system and should make sacrifice for taxation of their income and land etc
Hamza
how have the nations tries to solve the problem of scarcity in their economies?
Amani Reply
total concentration on to reduce the per unit cost of commodity by technically or whatever
Hamza
explain what will happen to producer of green coconut now that we have to lockdown in the kingdom of tonga
Tuha Reply
the demand for coconut will decrease and supply increases which result in the decrease in the price of coconut and the coconut will be more elastic
Hamza
tonga is producing more long run economic good explain the meaning of the statement and its implication on the tonga economy
Tuha Reply
Demand is the various quantities of goods and services that consumer(s)are willing and able to purchase at a price within a time
Muhammad Reply
What is demand
Mc Reply
demand relates with the need of people for their satisfaction.
Mohd
demand is de amount of goods and services a consumer us willing to purchase at a given price over a given period of time
Osei
riDemand is the amount of good and services which consumers are willing and able to buy at a particular peroid of time and at a given price
Miguel
Yes that is the tire thing
samuel
Demand is the quantity of goods and services which consumers are willing and able to purchase at a given price over a period of time
Sundaybha
simply , Demand is the sum up of 1)- desire of the commodity 2)- purchasing power for that commodity
Hamza
demand is the amount of goods and service wen consumers are willing and able to buy them at a give time
Dora
Distinguish between cross elasticity and income elasticity of demand
Ruth Reply
Distinguish between cross elasticity and income elasticity of demand
Ruth
if change in the demand of the commodity with respect to change in demand of the substitute or other product called cross elasticity
Hamza
and. if change in the demand of the commodity due to change in the income . called income elasticity
Hamza
👍
Vipul
Cross elasticity of demand is the degree of responsiveness of quantity demanded of a commodity to a small change in price of another commodity whiles Income elasticity of demand is the degree of responsiveness of quantity demanded of a commodity to a small change in income of it's consumers
Afriyie
but these are book wordings
Hamza
income elasticity of demand shows how quantity demanded changes due to changes in income on the other hand cross elasticity refers to how the quantity demanded of a particular good alers given a change in the price of another good.
Keysie
what is the competitive demand
Adiza Reply
Income
Sanni
Competitive demand are those commodity dat are competitive in nature e.g the close up and my my toothpaste the increase in price of close up may bring abt decrease in demand of it and it will serve as increase in purchase of my my
Daniel
With regards to coal shortage and manicipal debts the what form of intervention do you think Eskom can put in place.
kedibone Reply
economic growth of Bhutan
Nima Reply
please, explain all the mathematics terms used in economics
nelson
The answer is: little more than high school algebra and graphs.
Tere
waht is hydrating power of lithium carbonates
Mahar Reply

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Source:  OpenStax, Chemistry of the main group elements. OpenStax CNX. Aug 20, 2010 Download for free at http://cnx.org/content/col11124/1.25
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