Answer:
b) 2.0 mol
Explanation:
Given data:
Number of moles of Ca needed = ?
Number of moles of water present = 4.0 mol
Solution:
Chemical equation:
Ca + 2H₂O → Ca(OH)₂ + H₂
now we will compare the moles of Ca and H₂O .
H₂O : Ca
2 : 1
4.0 : 1/2×4.0 = 2.0 mol
Thus, 2 moles of Ca are needed.
Answer:
The coordination sphere of a complex consists of <u><em>the central metal ion and the ligands bonded to it.</em></u>
Explanation:
The Coordination Compounds are sets of a central metal ion attached to a group of molecules or ions that surround it. They are also called metal complexes or simply complexes. Then they are compounds that have a central atom surrounded by a group of molecules or ions, the latter called ligands.
The central atom must have empty orbitals capable of accepting pairs of electrons, with the transition metals being the ones with the greatest tendency. Because of this, they can act as Lewis acids (electron pair acceptors). The ligands have unshared electron pairs, then acting as Lewis bases (electron pair donors).
When forming a complex, it is said that the ligands coordinate to the metal and the central metal and the ligands attached to it constitute the coordination sphere of the complex.
Finally, <u><em>the coordination sphere of a complex consists of the central metal ion and the ligands bonded to it.</em></u>
It is a graph. It shows observations and then you record your results with any of the graph types.
The elements in a periodic table are arranged in the increasing order of their atomic number.