This will take you to the main part of Chemguide. To return to the list of all the CIE sections To return to the list of learning outcomes in Section 9.5 It is a soft silver-white alkaline earth metal that is highly reactive and occurs. That means that you can fit a lot more iron atoms into a given volume than calcium atoms. Calcium is a chemical element with the symbol Ca and atomic number 20. The radius of a calcium atom is 0.197 nm the radius of an iron atom is only 0.126 nm. Iron atoms are significantly smaller than calcium atoms. The relative atomic mass of calcium is 40, but the RAM of iron is 56, for example. Calcium (Ca) is a vital element that aids our bones stay tough and capable of supporting our load. Iron is fairly typical with a density of 7.89 g cm -3.Īs you go across the period, the atoms get heavier. What is Calcium Calcium with atomic number 20 is represented in the periodic table with the symbol Ca. All living organisms require calcium for survival. Calcium is the fifth most abundant element by mass (3.4) in both the Earth's crust and in seawater. It is a group 2 metal, also known as an alkaline-earth metal, and no populated d-orbital electrons. The transition elements have higher densities than calcium. Calcium is the 20th element in the periodic table. Zinc's 3d electrons aren't involved because the 3d level is then full.Ĭalcium's density is quite low at 1.54 g cm -3. With scandium and the transition metals, 3d electrons are involved as well. In calcium, only the 4s electrons are involved. This is because one of the factors which control melting point is the number of electrons which are involved in the metallic bond. Calcium is a soft alkaline earth metal, one of the most abundant. They include beryllium (Be), magnesium (Mg), calcium (Ca). All of the transition metals following it in the Periodic Table have higher melting points (apart from zinc, which doesn't count as a transition metal). You will need a vector editing program to open/edit this EPS image. Group 2 elements are elements in the periodic table that are part of the alkaline earth metal group. (In fact the modern IUPAC definition of a transition element would include scandium, but that isn't what the CIE syllabus is using.)Ĭalcium's melting point is variously quoted as 839☌ or 842☌. What is CA meaning in Chemistry 20+ meanings of CA abbreviation related to Chemistry: Vote. Remember that the d-block elements include everything from scandium to zinc, but scandium and zinc themselves don't count as transition elements.
The syllabus actually compares calcium with the transition metals, but there are several cases where it is easier to compare it with the whole of the first row of d-block elements - especially for explanations.
CA ELEMENT CHEMISTRY SERIES
The syllabus quotes calcium for comparison purposes because it is immediately before the first transition series in the Periodic Table. This statement asks you to compare the melting point and density of a typical transition metal with a non-transition metal like calcium.īefore you go on, you should find and read the statement in your copy of the syllabus. Chemguide: CIE A level chemistry support: Learning outcome 9.5(c)Ĭhemguide: Support for CIE A level Chemistry
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