Spectrophotometry

MS adduct m/z calculator

Formula or mass to adduct m/z, and reverse-match an observed peak by ppm.

m/z = (M·n + adduct) / z
If given, the neutral monoisotopic mass is computed from it.
Protocol result
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MS adduct m/z calculator · m/z = (M·n + adduct) / z · the lab bench, calculated
MS adducts✓ m/z = (M·n + adduct) / z
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Closest adduct: [2M+H]+ at m/z 361.1341 (-169283.5 ppm).

1

Neutral monoisotopic mass: 180.0634 Da.

Adductm/zppm
[M+H]+181.0707+656811.7
[M+Na]+203.0526+477449.6
[M+K]+219.0265+369697
[M+NH4]+198.0966+514412.9
[M+2H]2+91.039+2295292.1
[M+H-H2O]+163.0601+839812.4
[2M+H]+361.1341-169283.5
⚠

Closest adduct to m/z 300: [2M+H]+ at 361.1341 (-169283.5 ppm). Over 10 ppm: confirm the formula and instrument calibration.

Neutral mass
180.0634 Da
Polarity
pos
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