here, it says to calculate the mass percent of carbon within sodium carbonate, So sodium carbonate is N a to C 03 We're looking for the mass percent off carbon, so that means we're gonna need the grams of carbon over the grams of the compound itself. Times 100. Alright, so sodium carbonate has within it to sodium one carbon and three oxygen's. We're gonna multiply them each by their atomic masses from the periodic table. So sodium is 22.99 g, carbon is 12.1 g and oxygen is g. So multiplying them out, we get 50 45.98 g, 12.1 g and 48 g. Add them all together. That comes out to 105.99 g. Take those numbers. So for carbon, it's Mass is 12 01 and for the compound itself, it's 105.99 So we do 12.1 divided by 105.99 When we do that, we get 11.3% as the mass percent of carbon within sodium carbonate