Two reactants combine to form one new product. which of the following best describes this type of chemical reaction? combustion synthesis decomposition single replacement

32.06% yield
explanation:
first, calculate theoretical yield of carbonic acid
balanced equation: 2nahco3 → na2co3 + h2co3
step 1: convert 3.24 grams nahco3 to moles nahco3 by dividing by molar mass
          - 3.24 g nahco3 / (22.99 + 1.008 + 12.01 + 3(15.999)) g/mol nahco3 = 0.039         moles
step 2: use mol: mol ratio to convert moles nahco3 to moles h2co3
          - 0.039 mol nahco3 x 1 mol h2co3 / 2 mol nahco3 = 0.0195 moles h2co3
step 3: convert to grams h2co3 by multiplying by molar mass
          - 0.0195 moles h2co3 x ( 2(1.008) + 12.01 + 3(15.999)) = 1.209 grams h2co3
second: calculate the actual yield of carbonic acid, using the (3.24 - 2.19) 1.05 grams nahco3 that actually decomposed.
step 1: convert 1.05 grams nahco3 to moles nahco3 by dividing by molar mass
          - 1.05 g nahco3 / (22.99 + 1.008 + 12.01 + 3(15.999)) g/mol nahco3 = 0.0125 moles
step 2: use mol: mol ratio to convert moles nahco3 to moles h2co3
          - 0.0125 mol nahco3 x 1 mol h2co3 / 2 mol nahco3 = 0.0063 moles h2co3
step 3: convert to grams h2co3 by multiplying by molar mass
          - 0.0063 moles h2co3 x ( 2(1.008) + 12.01 + 3(15.999)) = 0.388 grams h2co3
third: calculate percent yield by dividing actual yield by theoretical yield, and multiplying by 100
0.388 g h2co3 / 1.209 g h2co3 (x 100%) = 32.06% yield.