Answer:
there is no d electron that can be promoted via the absorption of visible light
Explanation:
One of the properties of transition elements is the possession of incompletely filled d orbitals. This property accounts for their unique colours.
The colours of transition metal compounds stem from d-d transition of electrons due to the presence of vacant d orbitals of appropriate energy to which electrons could be promoted.
For elements whose atoms have a d10 configuration, such vacant orbitals does not exist hence their compounds are not colored.
Sometimes, the colour of transition metal compounds stem from ligand to metal charge transfer(LMCT) for instance in KMnO4.
Well you have to mix chemicals which caused a chemical reaction. When you mix salt and ice the freezing point of liquid changes. the ice gets colder
Answer:
The first ionization energy for K is less than Ca because Ca has a larger effective nuclear charge.
For the first one the answer is B. and the second one is D.
There are multiple factors that contribute to the cost of a mineral.
First of all is the demand or application, which will be related to its
physical properties. For example, nontarnishing metals like gold are
held in high value for their appearance. Second is the supply of the
mineral, those that only have a small quantity in the earth's crust are
likely to be more expensive. Third is the cost of extraction and
manufacturing. Some minerals may be abundantly found, but may be
distributed over a wide area, meaning that it is still expensive to mine
and transport.