Naphthenic Acids: Formation, Role in Emulsion Stability, and Recent Advances in Mass Spectrometry-Based Analytical Methods

Table 1

Expected even-electron ions ([M-57]⁺) for homologous series of t-butyldimethylsilylated naphthenic acids [104].

Carbon number (n)	Nominal mass for [M-57]^+ ion
	Z = 0	Z = −2	Z = −4	Z = −6	Z = −8	Z = −10	Z = −12
6	173	171	—	—	—	—	—
7	187	185	—	—	—	—	—
8	201	199	—	—	—	—	—
9	215	213	211	—	—	—	—
10	229	227	225	—	—	—	—
11	243	241	239	—	—	—	—
12	257	255	253	251	—	—	—
13	271	269	267	265	—	—	—
14	285	283	281	279	—	—	—
15	299	297	295	293	291	—	—
16	313	311	309	307	305	—	—
17	327	325	323	321	319	—	—
18	341	339	337	335	333	331	329
19	355	353	351	349	347	345	343
20	369	367	365	363	361	359	357
21	383	381	379	377	375	373	371
22	397	395	393	391	389	387	385
23	411	409	407	405	403	401	399
24	425	423	421	419	417	415	413
25	439	437	435	433	431	429	427
26	453	451	449	447	445	443	441
27	467	465	463	461	459	457	455
28	481	479	477	475	473	471	469
29	495	493	491	489	487	485	483
30	509	507	505	503	501	499	497
31	523	521	519	517	515	513	511
32	537	535	533	531	529	527	525
33	551	549	547	545	543	541	539