Which one of the following statements about orbitals is INCORRECT? 1) orbitals are regions in space where one is likely to find an electron

2) orbitals can hold up to two electrons

3) orbitals can hold two electrons provided they are spinning in the same direction

4) s, p, d and f orbitals are possible

3) orbitals can hold two electrons provided they are spinning in the same direction

We define an orbital in chemistry as a region in space where there is a high probability of finding an electron.

Each orbital holds a maximum of two electrons which spin in opposite direction according to Pauli exclusion principle.

According to this principle no two electrons can have the same set of quantum numbers. As a result, the spin quantum numbers of two electrons in the same orbital must differ hence they spin in opposite directions.

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it's c. elements are placed in rows based on how may valencies electrons have.