3. How many significant figures are in the number 805000? *

Answer. First things first... Balance the Chemical Equation

2FeCl3 + 3(NH4)2CO3 > 6NH4Cl + Fe2(CO3)3

Its balanced Now.

200g of FeCl3 ---Given this... We can get jts reacting Moles

Mole = Mass/Molar Mass

Molar Mass of FeCl3 = 56 + (35.5)x3=162.5gmol-¹

Mole=200/162.5 =1.231moles of FeCl3

From the equation of Reaction

When 2mole of FeCl3 reacts It produces 1mole of Iron III carbonate [Fe2(CO3)3]

Since Mole ratio of reaction between both is 2:1

Therefore When 1.231moles of FeCl3 react

1.231/2 moles of Fe2(CO3)3 will be produced.

= 1.231/2 = 0.616moles.

0.616Moles of Fe2(CO3)3 will be produced

Recall MASS =MOLE X MOLAR MASS

MOLAR MASS OF FE2(CO3)3= 56(2) + (60)(3)=292gmol-¹

MASS = 0.616 x 292 =179.872g ~ 180g of Fe2(CO3)3 Will Be Produced.

OPTION A SEEMS TO BE THE CLOSEST. THAT SHOULD BE OUR ANSWER. I MAY HAVE MISSED IT A BIT BECAUSE OF SOME APPROXIMATIONS.

BYE!