Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Chemical class | Group | Formula | Prefix | Suffix |
| --- | --- | --- | --- | --- |
| Thiol | Sulfhydryl | RSH | sulfanyl- (-SH) | -thiol |
| Sulfide ( Thioether ) | Sulfide | RSR' | substituentsulfanyl- (-SR') | di(substituent)sulfide |
| Disulfide | Disulfide | RSSR' | substituentdisulfanyl- (-SSR') | di(substituent)disulfide |
| Sulfoxide | Sulfinyl | RSOR' | -sulfinyl- (-SOR') | di(substituent)sulfoxide |
| Sulfone | Sulfonyl | RSO 2 R' | -sulfonyl- (-SO 2 R') | di(substituent)sulfone |
| Sulfinicacid | Sulfino | RSO 2 H | sulfino- (-SO 2 H) | -sulfinicacid |
| Sulfonicacid | Sulfo | RSO 3 H | sulfo- (-SO 3 H) | -sulfonicacid |
| Thiocyanate | Thiocyanate | RSCN | thiocyanato- (-SCN) | substituentthiocyanate |
| Thiocyanate | Isothiocyanate | RNCS | isothiocyanato- (-NCS) | substituentisothiocyanate |
| Thione | Carbonothioyl | RCSR' | -thioyl- (-CSR') or sulfanylidene- (=S) | -thione |
| Thial | Carbonothioyl | RCSH | methanethioyl- (-CSH) or sulfanylidene- (=S) | -thial |
Question:
Which formula has a thial as a chemical class?
Answer:
RCSH