The mineral benitoite is a gemstone for making jewelry. it has a molecular weight of 413.44 grams/mole and a percent composition of 33.21% ba, 11.58% ti, 20.38% si, and 34.83% o. what is the molecular formula? a. batisi3o9 b. ba2tisi2o3 c. batisi3o6 d. batisi6o9

               Option-A (BaTiSi₃O₉)

Step 1: Calculate Moles of each Element;

                      Moles of Ba  =  %Ba ÷ At.Mass of Ba

                      Moles of Ba  = 33.21 ÷ 137.33

                      Moles of Ba  =  0.241 mol

                      Moles of Ti  =  %Ti ÷ At.Mass of Ti

                      Moles of Ti  = 11.58 ÷ 47.88

                      Moles of Ti  =   0.241 mol

                      Moles of Si  =  %Si ÷ At.Mass of Si

                      Moles of Si  = 20.38 ÷ 28.09

                      Moles of Si  =  0.725 mol

                      Moles of O  =  %O ÷ At.Mass of O

                      Moles of O  = 34.83 ÷ 16.0

                      Moles of O  =  2.176 mol

Step 2: Find out mole ratio and simplify it;

       Ba                            Ti                                Si                          O

     0.241                       0.241                          0.725                    2.176

 0.241/0.241           0.241/0.241                0.725/0.241            2.176/0.241

         1                             1                                    3                           9 

Hence,  Empirical Formula  =  BaTiSi₃O₉

Step 3: Calculating Molecular Formula:

Molecular formula is calculated by using following formula,

                    Molecular Formula  =  n × Empirical Formula   (1)

Also, n is given as,

                     n  =  Molecular Weight / Empirical Formula Weight

Molecular Weight  =  413.44 g.mol⁻¹

Empirical Formula Weight  =  137.33 (Ba) + 47.88(Ti) + 28.09 (Si₃) + 16 (O₉)  =  413.48 g.mol⁻¹

So,

                     n  =  413.44 g.mol⁻¹ ÷ 413.48 g.mol⁻¹

                     n  =  1

Putting Empirical Formula and value of "n" in equation 1,

                    Molecular Formula  = 1 × BaTiSi₃O₉

                   Molecular Formula  =  BaTiSi₃O₉

A.  

BaTiSi3O9

Explanation:

the molecular formula for the mineral benitoite is  BaTiSi3O9

drop a like if is life

your answer would be a. 12.5 kg

most historians agree that gabriel mouton, the vicar of st. paul’s church in lyons, france, is the “founding father” of the metric system. he proposed a decimal system of measurement in 1670. mouton based it on the length of one minute of arc of a great circle of the earth (now called a nautical mile, 1852 meters). he also proposed the swing-length of a pendulum with a frequency of one beat per second as the unit of length (about 25 cm). a pendulum beating with this length would have been fairly easy to produce, thus facilitating the widespread distribution of uniform standards. over the years, his work was revised, improved, and extended by a number of french scientists.

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