Aspirin (C9H8O4) is synthesized by reacting salicylic acid (C7H6O3) with acetic anhydride (C4H6O3). The balanced equation is given below.

C7H6O3 + C4H6O3 C9H8O4 + HC2H3O2

What mass of acetic anhydride is needed to completely consume 3.60 x 10^2 g salicylic acid?

i worked out the problem and got 270 but the answer is 370. here is my work.

360g C7H6O3 x 1 mol C7H6O3/138.118 g C7H6O3 x 1 mol C4H6O3/ 1 mol C7H6O3 x 102.088 g C4H6O3/1 mol C4H6O3 = 270g C4H6O3

sorry that looks really confusing but is there something wrong with my conversion factor??

Your work would not look so confusing if you used parentheses. For example,

360 g C6H7O3 x (1 mol C6H7O3/138.118) x .....
Your work looks ok, however, I ran this on my calculator and obtained 266.08 grams. (I also used 138.123 instead of 138.118 but I don't think that will make any significant difference). Are you keying this into a database? If so, and 266 doesn't work, I would try 2.66 x 10^2 since the problem was given in scientific notation.

I agree with you, mol masses 138 and 102

C7H6O3 + C4H6O3 ---> C9H8O4 + HC2H3O2
360/138 or 2.61 mole of C7H6O3
and therefore
2.61 mol of C4H6O3
2.61 = x/102
x = 267
(I did not carry all the decimal places)

I agree with you, mol masses 138 and 102

C7H6O3 + C4H6O3 ---> C9H8O4 + HC2H3O2
360/138 or 2.61 mole of C7H6O3
and therefore
2.61 mol of C4H6O3
2.61 = x/102
x = 267
(I did not carry all the decimal places)

Your work would not look so confusing if you used parentheses. For example,

360 g C6H7O3 x (1 mol C6H7O3/138.118) x .....
Your work looks ok, however, I ran this on my calculator and obtained 266.08 grams. (I also used 138.123 instead of 138.118 but I don't think that will make any significant difference). Are you keying this into a database? If so, and 266 doesn't work, I would try 2.66 x 10^2 since the problem was given in scientific notation.

360g C7H6O3 x 1 mol C7H6O3/138.118 g C7H6O3 x 1 mol C4H6O3/ 1 mol C7H6O3 x 102.088 g C4H6O3/1 mol C4H6O3 = 270g C4H6O3

Your conversion factors appear to be correct. Based on your calculations, you have determined that 360g of salicylic acid requires 270g of acetic anhydride. However, the correct answer given is 370g of acetic anhydride.

To double-check your work, let's go through the calculations again:

Given:
Mass of salicylic acid = 360g

To find:
Mass of acetic anhydride required

Balanced equation:
C7H6O3 + C4H6O3 -> C9H8O4 + HC2H3O2

Let's calculate the molar masses of the compounds involved:
Salicylic acid (C7H6O3) = 138.118 g/mol
Acetic anhydride (C4H6O3) = 102.088 g/mol

Now let's set up the conversion:

360g C7H6O3 * (1 mol C7H6O3 / 138.118 g C7H6O3) * (1 mol C4H6O3 / 1 mol C7H6O3) * (102.088 g C4H6O3 / 1 mol C4H6O3)

Calculating this expression will indeed give you the correct answer of 270g.

It seems that there might be an error in the given answer. Your calculations are correct, and the mass of acetic anhydride needed to completely consume 360g of salicylic acid is indeed 270g, not 370g.