What is conserved in this chemical reaction

[From: ] [author: ] [Date: 12-03-28] [Hit: ]

N2 (g) + 3F2 (g) -----> 2NF3 (g)
Please help me. This is for a chem review due tomorrow and I don't understand this question!

mass
energy
charge

http://www.kentchemistry.com/links/Math/…

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