Hoi

Hoi,  ₂He

ngoi-kôn
colorless gas, exhibiting a red-orange glow when placed in a high-voltage electric field Spectral lines of helium
Kî-pún sin-sit
Miàng, fù-ho	Hoi, He
Yîn-ngî	helium
ngoi-hìn	colorless gas, exhibiting a red-orange glow when placed in a high-voltage electric field
Hoi chhai chû-khì-péu ke vi-chi
– ↑ He ↓ Ne Khiâng ← Hoi → Lithium
ngièn-chṳ́ sì-sú	2
ngièn-chṳ́-liòng (±)	4.002602(2)
ngièn-su lui-phe̍t	hî-yù hi-thí
Chhu̍k, fûn-khî	18 chhu̍k, s-block
chû-khì	period 1
thien-chṳ́ phài-lie̍t	1s2
per shell	2
vu̍t-lî sin-chṳt
Siông	hi-thí
yùng-tiám	0.95 K ​(−272.20 °C, ​−457.96 °F) (at 2.5 MPa)
pui-tiám	4.222 K ​(−268.928 °C, ​−452.070 °F)
me̍t-thu at stp (0 °C and 101.325 kPa)	0.1786 g·L−1
0.145 g·cm−3
0.125 g·cm−3
Sâm-siong-tiám	2.177 K, ​5.043 kPa
lìm-kie-tiám	5.1953 K, 0.22746 MPa
Yùng-fa-ngie̍t	0.0138 kJ·mol−1
Chîn-fat-ngie̍t	0.0829 kJ·mol−1
Ngie̍t-yùng-liong	20.78 J·mol−1·K−1
chîn-hi-ap (defined by ITS-90) P (Pa) 1 10 100 1 k 10 k 100 k chhai T (K)     1.23 1.67 2.48 4.21
Ngièn-chṳ́ sin-chṳt
Yông-fa-su	0
Thien-fu-sin	Pauling scale: no data
Thien-lì-nèn	1st: 2372.3 kJ·mol−1 2nd: 5250.5 kJ·mol−1
Khiung-ka pan-kang	28 pm
Van der Waals pan-kang	140 pm
Miscellanea
Chîn-thí keu-chho	​hexagonal close-packed (hcp)
Sâng-suk	972 m·s−1
Ngie̍t-chhòn-thô-li̍t	0.1513 W·m−1·K−1
Chhṳ̀-sin	diamagnetic
CAS Registry Number	7440-59-7
Le̍k-sú
Hí-miàng	after Helios, Greek god of the Sun
Fat-hien	Pierre Janssen, Norman Lockyer (1868)
First isolation	William Ramsay, Per Teodor Cleve, Abraham Langlet (1895)
Chui vún-thin ke thùng-vi-su
Chú vùn-chông: Hoi ke thùng-vi-su
iso NA half-life DM DE (MeV) DP 3He 0.000137%* 3He is stable with 1 neutron 4He 99.999863%* 4He is stable with 2 neutrons
* Atmospheric value, abundance may differ elsewhere

Hoi

Hoi (氦), fe̍t-chá ham-cho Yòng (氜), he yit-tsúng Fa-ho̍k Ngièn-su, fa-ho̍k fù-ho vì He, ngièn-tsṳ́ su-muk he 2.