The properties of compounds are (what?) to the elements that make it up. *

A compound is a unique substance that forms when two or more elements combine chemically. A compound always has the same elements in the same proportions. The properties of compounds may be very different from the properties of the elements that form them. Some compounds form rigid frameworks called crystals.

Explanation:

An element or compounds’ physical properties are far easier to detect. These properties are things that can be observed without changing the identity of the element or compound. These properties include color, smell, freezing point, boiling point, melting point, opacity, viscosity, and density.

Explanation:

"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"