Baking cake and only have half of what need for white sugar. Have tons brown though
What's the recipe? It should work! I would substitute by weight rather than volume. The flavor might be a bit different but I bet it will be just as delicious.
Shouldn't be a problem- brown sugar has more moisture, which can effect recipes, but most cakes have enough moisture that it won't be very significant. I would recommend measuring by volume rather than weight (be sure to pack the brown sugar tightly) since the moisture makes brown sugar heavier.
I LOVE substituting brown sugar for white sugar in recipes. If I think it will suit the flavor, I do it all the time. You may need to bake it a little longer, but not too much longer. In my chocolate and carrot cake recipes, I have switched completely to brown and will never go back. Sometimes, for extra depth, I'll switch it out in my butter cake.
As was mentioned, make sure you make the substitution by weight or find a reputable source for volumetric conversion.