The diagram below shows part of the rock cycle.

Rock cycle with a volcanic eruption at the top. Moving counterclockwise, there is an arrow pointing to Rock B. From Rock B there is an arrow labeled sediment and compaction pointing to Rock C. From Rock C there is an arrow labeled heat and pressure pointing to Rock A. From Rock A there is an arrow labeled magma pointing back to volcanic eruption.

Which type of rock does C represent?

the law of conservation of mass states that in a chemical reaction, the total mass of reactants is equal to the total mass of products. because atoms are only rearranged in a chemical reaction, there must be the same number of sodium atoms and chlorine atoms in both the reactants and products

we can conclude that the melting point of table salt is above room temperature (it's actually 801 deg c). the melting point of mercury must be below room temperature (- 39 deg 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"