How many orbitals does d-subshell have ?
In chemistry and atomic physics, an electron shell, or a principal energy level, may be thought of as an orbit followed by electrons around an atom's nucleus. Each shell can contain only a fixed number of electrons: The first shell can hold up to two electrons, the second shell can hold up to eight (2 + 6) electrons, the third shell can hold up to 18 (2 + 6 + 10) and so on. Each shell consists of one or more subshells, and each subshell consists of one or more atomic orbitals.
Each subshell is constrained to hold 4ℓ + 2 electrons at most, namely: