Answer:- D. 1.8 moles of Fe and
.
Solution:- The balanced equation is:

let's first figure out the limiting reactant using the given moles and mol ratio:

= 5.4 mol CO
From calculations, 5.4 moles of CO are required to react completely with 1.8 moles of Iron(III)oxide but only 2.7 moles of CO are available. It means CO is limiting reactant.
Products moles depends on limiting reactant. Let's calculate the moles of each reactant formed for given 2.7 moles of CO.

= 1.8 mol Fe

= 
So, the correct choice is D. 1.8 moles of Fe and
are formed.
Answer:6.94
Explanation:
Molar mass of CaCO3=40+12+16×3
=40+12+48=100g/mol
Moles=mass of substance/molar mass
=97mg/100g=0.097/100=0.00097moles/L.
PH=-log[CaCo3]=-log(0.00097)=6.94
P.s it's log to base e
Thus, sound will travel at a slower rate in the denser object. If sound waves of the same energy were passed through a block of wood and a block of steel, which is more dense than the wood, the molecules of the steel would vibrate at a slower rate. Thus, sound passes more quickly through the wood, which is less dense.
Your answer is going to be 200g