Question

aluminum hydroxide (al(oh)₃) is an active ingredient in antacids, which are prescribed to relieve indigestion and heartburn. how many moles of al(oh)₃ are in 15.5 grams of al(oh)₃? refer to a periodic table. write your answer to the correct number of significant figures. round if necessary. moles

Explanation:

Step1: Calculate molar mass of Al(OH)₃

The molar mass of Al is 26.98 g/mol, O is 16.00 g/mol, and H is 1.01 g/mol. For Al(OH)₃, molar mass $M = 26.98+(16.00 + 1.01)\times3=26.98 + 51.03=78.01$ g/mol.

Step2: Calculate moles of Al(OH)₃

Use the formula $n=\frac{m}{M}$, where $m = 15.5$ g and $M = 78.01$ g/mol. So $n=\frac{15.5}{78.01}\approx0.199$ mol.

Answer:

0.199