Liquid Solution

At \(T(\mathrm{~K}) \times \mathrm{g}\) of a non-volatile solid (molar mass \(78 \mathrm{~g} \mathrm{~mol}^{-1}\)) when added to 0.5 kg water, lowered its freezing point by \(1.0^{\circ} \mathrm{C}\). What is \(x\) (in g)? (\(K_f\) of water at \(T(\mathrm{~K})=1.86 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}\))