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The transport properties in the mixed state of high-quality Ca
0.8
La
0.2
Fe
0.98
Co
0.02
As
2
single crystal, a newly discovered 112-type iron pnictide superconductor, are comprehensively studied by magneto-resistivity measurement. The field-dependent activation energy,
U
0
, is derived in the framework of thermally activated flux flow (TAFF) theory, yielding a power law dependence
U
0
~
H
α
with a crossover at a magnetic field around 2 T in both
H
⊥
ab
and
H
//
ab
, which is ascribed to the different pinning mechanisms. Moreover, we have clearly observed the vortex phase transition from vortex-glass to vortex-liquid according to the vortex-glass model, and vortex phase diagrams are constructed for both
H
⊥
ab
and
H
//
ab
. Finally, the results of mixed-state Hall effect show that no sign reversal of transverse resistivity
ρ
xy
(
H
) is detected, indicating that the Hall component arising from the vortex flow is also negative based on the time dependent Ginzburg-Landau (TDGL) theory. Meanwhile, the transverse resistivity
ρ
xy
(
H
) and the longitudinal resistivity
ρ
xx
(
H
) follow the relation |
ρ
xy
(
H
)|=
Aρ
xx
(
H
)
β
well with an exponent
β
~2.0, which is in line with the results in theories or experiments previously reported on some high-
T
c
cuprates.