NH4 or NH 4 or NH-4 may refer to:
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Ammonium
Ammonium is a modified form of ammonia that has an extra hydrogen atom. It is a positively charged (cationic) polyatomic ion, molecular ion with the chemical formula or . It is formed by the protonation, addition of a proton (a hydrogen nucleu ...
, the cation in chemistry
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National Highway 4 (India), new numbering for a National Highway in India
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National Highway 4 (India, old numbering)
Route 4, or Highway 4, may refer to several highways in the following countries:
International
* AH4, Asian Highway 4
* European route E04
* European route E004
* Cairo – Cape Town Highway
Albania
* SH-4 road in Albania from Durrës to Ka ...
, a major National Highway in western and southern India
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New Hampshire Route 4, a short state highway located in eastern Strafford County, New Hampshire, United States
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