Agraduated cylinder is filled to 8.0 ml and a piece of granite is placed in the cylinder, displacing the level to 14.6 ml. what is the volume of the granite piece in cubic centimeters?

Answer is: the volume of the granite piece is 6.6 cubic centimeters.

V(graduated cylinder) = 8.0 mL; volume of a filled gratuated cylinder.

V(graduated cylinder + piece of granite) = 14.6 mL.

V(piece of granite) = V(graduated cylinder + piece of granite) - V(graduated cylinder).

V(piece of granite) = 14.6 mL - 8.0 mL.

V(piece of granite) = 6.6 mL = 6.6 cm³.

One millimetre (mL) = one cubic centimetre (cm³).

the answer is definitely c.

"you start with 15.67 g mgco3-xh2o, when heated and all the water is removed, you are left with 7.58 g mgco3 only.

therefore, you had 15.67 - 7.58 = 8.09g h2o  

moles of each :

7.58g mgco3 = ? moles = 7.58g / 83.4g/mole = 0.09moles  

8 09g h2o = ? moles = 8.09g / 18g/mole = 0.44moles  

molar ratio between the two by dividing both numbers by the smallest number :

0.09 / 0.09 = 1  

0.44 / 0.09 = 4.8  

mgco3-5h2o"