What is a joule second?(not per second)ie:planks constant.
Why do s orbitals (l=0)have zero angular momentum?
A joule second (J·s) is the unit of measure for the physical quantity known as angular momentum. It is commonly used to express the value of Planck's constant (h), which is an important constant in quantum mechanics.
To understand why s orbitals with l=0 have zero angular momentum, we need to dive into the concept of angular momentum in quantum mechanics. In quantum mechanics, the angular momentum is quantized, meaning it can only take on certain discrete values.
The angular momentum of an electron in an atom is described by three quantum numbers: l, m_l, and s. The l quantum number corresponds to the shape of an orbital, m_l represents the orientation of the orbital in space, and s represents the electron spin.
The l quantum number can have integer values from 0 up to (n-1), where n is the principal quantum number. The s orbital corresponds to l=0, which means it has a spherical shape. In this case, the electron's angular momentum is zero because there is no rotational motion involved in a spherical orbital. Hence, s orbitals have zero angular momentum.
This can be further explained by considering the mathematical expression for the angular momentum operator. The angular momentum operator, denoted as L^2, is given by L^2 = l(l+1)ħ², where ħ is the reduced Planck's constant (h/2π). When l=0, the angular momentum becomes zero since 0(0+1) is zero.
In summary, the s orbitals (l=0) have zero angular momentum because of their spherical shape, which leads to no rotational motion. This is in line with the principles of quantum mechanics and the quantization of angular momentum.