  The abundances of low First Ionisation Potential (FIP) elements are three to
four times higher (FIP bias) in the closed loop active corona than in the
photosphere, known as the FIP effect. Observations suggest that the abundances
vary in different coronal structures. Here, we use the soft X-ray spectroscopic
measurements from the Solar X-ray Monitor (XSM) on board the Chandrayaan-2
orbiter to study the FIP effect in multiple A-class flares observed during the
minimum of solar cycle 24. Using time-integrated spectral analysis, we derive
the average temperature, emission measure, and the abundances of four elements
- Mg, Al, Si, and S. We find that the temperature and emission measure scales
with the flares sub-class while the measured abundances show an intermediate
FIP bias for the lower A-flares (e.g., A1), while for the higher A-flares, the
FIP bias is near unity. To investigate it further, we perform a time-resolved
spectral analysis for a sample of the A-class flares and examine the evolution
of temperature, emission measure, and abundances. We find that the abundances
drop from the coronal values towards their photospheric values in the impulsive
phase of the flares, and after the impulsive phase, they quickly return to the
usual coronal values. The transition of the abundances from the coronal to
photospheric values in the impulsive phase of the flares indicates the
injection of fresh unfractionated material from the lower solar atmosphere to
the corona due to chromospheric evaporation. However, explaining the quick
recovery of the abundances from the photospheric to coronal values in the decay
phase of the flare is challenging.
