  It is demonstrated, that chirality violating condensates in massless QCD
arise entirely from zero mode solutions of Dirac equations in arbitrary gluon
fields. The model is suggested, where the zero mode solutions are the ones for
quarks, moving in the instanton field. Basing on this model were calculated the
quark condensate magnetic susceptibilities of dimensions $3(\chi)$ and 5
($\kappa$ and $\xi$). The good considence of the values $\chi,\kappa$ and
$\xi$, obtained in this approach with ones, found from the hadronic spectrum ia
a serious argument in favour, that instantons are the only source of chirality
violating condensates in QCD. The temperature dependence of the quark
condensate is discussed. It is shown that the phase transition, corresponding
to the $T$-dependence of the quark condensate $\alpha(T)$ as an order
parameter, is of the type of crossover.
