A radial node is a region within an atomic orbital where the radial probability density of finding an electron is zero. The number of radial nodes for an atomic orbital is calculated using the formula:
[ Radial Nodes = n - l - 1 ]
where:
• (n) is the principal quantum number
• (l) is the azimuthal quantum number
Orbital analysis:
• 1s orbital: (n = 1), (l = 0). Radial nodes = 1 - 0 - 1 = 0.
• 2s orbital: (n = 2), (l = 0). Radial nodes = 2 - 0 - 1 = 1.
• 2p orbital: (n = 2), (l = 1). Radial nodes = 2 - 1 - 1 = 0.
• 3d orbital: (n = 3), (l = 2). Radial nodes = 3 - 2 - 1 = 0.
Based on these calculations, only the 2s orbital possesses a radial node; the 1s, 2p, and 3d orbitals do not.
Which of the following statements are true?
A. Unlike Ga that has a very high melting point, Cs has a very low melting point.
B. On Pauling scale, the electronegativity values of N and C are not the same.
C. $Ar, K^{+}, Cl^{–}, Ca^{2+} and S^{2–}$ are all isoelectronic species.
D. The correct order of the first ionization enthalpies of Na, Mg, Al, and Si is Si $>$ Al $>$ Mg $>$ Na.
E. The atomic radius of Cs is greater than that of Li and Rb.
Choose the correct answer from the options given below: