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 (+1076791.1 ppm).

1

Neutral monoisotopic mass: 180.0634 Da.

Adductm/zppm
[M+H]+181.0707+3142029.3
[M+Na]+203.0526+2693624.1
[M+K]+219.0265+2424242.5
[M+NH4]+198.0966+2786032.2
[M+2H]2+91.039+7238230.2
[M+H-H2O]+163.0601+3599531.1
[2M+H]+361.1341+1076791.1
⚠

Closest adduct to m/z 750: [2M+H]+ at 361.1341 (+1076791.1 ppm). Over 10 ppm: confirm the formula and instrument calibration.

Neutral mass
180.0634 Da
Polarity
pos
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