Answer:
coordination number
Explanation:
Coordination number -
In a crystal lattice , the number of atoms that are surrounded to a particular atom , is referred to as the coordination number of the crystal.
In the field of crystallography and chemistry , it is also called the ligancy.
In coordination chemistry , the number of ligands attached to the central metal atom is also known as the coordination number of the coordination compound.
Hence, from the given statement of the question,
The correct term is coordination number.
C. Groups 13-16 contain metalloids.
If you look on a periodic table, these usually have a different color.
Answer: The correct option is The properties of a noble gas.
Explanation: There are 7 periods in the periodic table.
The last element of each period are Helium (He), Neon (Ne), Argon (Ar), Krypton (Kr), Xenon (Xe), Radon (Rn) and Ununoctium (Uuo).
- The electronic configuration for Helium is
. For He, The outermost electrons are 2.
- The electronic configuration for all the other elements is
( where, n = 2, 3, 4, 5, 6 and 7 respectively). For all the other gases, the outermost electrons are 8.
All these elements have stable electronic configuration and are not reactive in nature. Hence, they are considered as noble gases.
Therefore, the last element of each period always have the properties of a noble gas.
3-ethyl-5,6-dimethyloctane
3-ethyl-2,3-dimethylpentane