Properties of a series of models with the same core mass and a varying initial core carbon abundance X_C, indicated with colors. (a) Duration of core carbon burning. (b) Final compactness as a function of X_C. Models that undergo convective core carbon burning are highlighted with black outlines. (c) Duration of the phase between core carbon depletion and core neon ignition as a function of m_C, the maximum mass coordinate reached by the carbon-burning front before core neon burning. The classical (M_Ch, 0) and effective (M_Ch) Chandrasekhar mass at core C depletion are shown as vertical dashed and full lines, respectively.