H2O (water) is a compound molecule.
Ca, Na, Mg are elemental metals.
NB
When writing elemental symbols;-
Single letter symbols are always a CAPITAL letter e.g. 'O' oxygen.
Double letter symbols are always written as , first letter is a capital letter and the second letter is lower/small case. e.g. 'Ca'( Calcium). Na(Sodium) , & Mg (Magnesium).
NOT as given with all capital letters.
Among the options listed, magnesium (Mg) is most similar to calcium (Ca) in terms of properties and roles in biological systems. Both are alkaline earth metals found in group 2 of the periodic table and play essential roles in maintaining proper function of muscles, nerves, and bones. Potassium (K), sodium (Na), and scandium (Sc) belong to different groups of the periodic table and have distinct properties compared to calcium.
The three main types of magma are basaltic magma, andesitic magma, and rhyolitic magma. They are classified according to their mineral composition. Basaltic magma is composed of SiO2 45-55 wt%, high in Fe, Mg, Ca, low in K, Na. Andesitic magma is composed of SiO2 55-65 wt%, intermediate. in Fe, Mg, Ca, Na, K. Rhyolitic magma is composed of SiO2 65-75%, low in Fe, Mg, Ca, high in K, Na.
Magnesium (Mg) is the largest atom among sulfur (S), sodium (Na), chlorine (Cl), and magnesium (Mg). This is because the size of an atom increases as you move down a group in the periodic table. Magnesium is located below the other elements in the periodic table, making it the largest atom among these options.
Of the following Elements;O,Si,Al,Fe,Ca,Na,K,Mg....which is the rarest single element in the Earth's crust?.....i say it's Mg because it is on 2% by weight of the Earth's crust.
The reaction between magnesium ions and sodium stearate would involve the magnesium ion (Mg^2+) displacing sodium (Na^+) in sodium stearate to form magnesium stearate and sodium ions. The equation can be represented as Mg^2+ + 2(C_17H_35COO^−) → Mg(C_17H_35COO)_2 + 2Na^+.
H2O. Notice the presence of two elements, H and O. Each of the other three is an element.
Hard Water (I think I'm not sure it's just a guess)
B-Al is different from the other pairs because it consists of elements from different groups in the periodic table. Li-Mg, Na-K, and Ca-Mg are pairs of elements from the same group which exhibit similar chemical characteristics.
Chlorides salts of Na, Mg, Ca.
Examples are Na+, K+, Mg+, Ca+, Cl-.
(Na, K, Ca, Mg, P, Fe, Cu, Zn, Mn and B
Metals as Al, Na, Fe, Ca, Mg, etc.
Li, Na, K, Rb, Cs, Fr, Be, Mg, Ca, Sr, Ba, Ra.
It is not typically endothermic; for example chlorides of Na, Ca, Mg etc. release heat.
crustal Rocks that consists of Ca,Al,Si, Na, K, Mg, Fe and O.
Are cations that cannot donate or accept protons and so they are neither acids or bases (e.g. Na+, K+, Ca++, Mg++) .
These salts are chlorides of Na, K, Mg, Ca.