Yttrium (Y)
Yttrium is element 39, a transition metal in group 3, period 5. A neutral atom has 39 protons, 50 neutrons and 39 electrons, 2 of them valence electrons.
Transition metal- Atomic number
- 39
- Atomic mass
- 88.906 u
- Valence electrons
- 2*
- Protons · neutrons
- 39 · 50
- Electrons per shell
- 2, 8, 18, 9, 2
- At room temperature
- solid
Bohr model of yttrium
The Bohr model draws yttrium as a nucleus of 39 protons and 50 neutrons, with its 39 electrons on 5 circular shells: 2 in shell 1, 8 in shell 2, 18 in shell 3, 9 in shell 4, 2 in shell 5. Press Build the atom to watch the shells fill from the inside out. The outer ring (the O shell) is dashed: the electrons there are the ones that take part in chemistry.
Real electrons don't travel in neat circles. They live in fuzzy orbitals, shown below, but the Bohr picture is the quickest way to count shells and valence electrons.
Electron configuration of yttrium
1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹
Short form (noble gas notation): [Kr] 5s² 4d¹. The [Kr] stands for the electrons of krypton, the noble gas before it.
How many valence electrons does yttrium have?
Yttrium has 2 valence electrons.
Yttrium is a transition metal, so its valence electrons are less clear-cut than for main-group elements. It has 2 electrons in its outermost shell (shell 5), and electrons in its inner d subshell can also take part in bonding.
Protons, neutrons and electrons
| Protons | 39 | equal to the atomic number |
|---|---|---|
| Electrons | 39 | equal to the protons in a neutral atom |
| Neutrons | 50 | mass number 89 − 39 protons |
Atoms of the same element can have different numbers of neutrons (isotopes). The count above uses the rounded atomic mass, the way it's taught in class.
Yttrium properties
| Symbol | Y |
|---|---|
| Category | Transition metal |
| Group · period · block | 3 · 5 · d |
| Atomic mass | 88.906 u |
| State at 25 °C | solid |
| Melting point | 1,795 K (1,520 °C, 2,770 °F) |
| Boiling point | 3,618 K (3,340 °C, 6,050 °F) |
| Density | 4.47 g/cm³ |
| Electronegativity (Pauling) | 1.22 |
| Atomic radius | 219 pm |
| First ionization energy | 6.217 eV |
| Electron affinity | 0.307 eV |
| Oxidation states | +3 |
| Common ion charge | +3 |
| Discovered | 1794 by Johan Gadolin |
Where yttrium sits on the periodic table
Group 3: Scandium.
Questions about yttrium
How many valence electrons does yttrium have?
Yttrium has 2 valence electrons in its outer shell; inner d or f electrons can also bond.
How many protons, neutrons and electrons does yttrium have?
A neutral yttrium atom has 39 protons and 39 electrons. Its most common form has about 50 neutrons (mass number 89 − 39 protons).
What is the electron configuration of yttrium?
1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹, written in short form as [Kr] 5s² 4d¹.
What does the Bohr model of yttrium look like?
A nucleus of 39 protons and 50 neutrons, circled by 5 electron shells holding 2, 8, 18, 9, 2 electrons.
What is the atomic number of yttrium?
39. The atomic number is the number of protons in the nucleus, and it is what makes an atom yttrium.