Someone wants to sell you a ring and claims that it is a diamond ring. Look at the data table below, and write a Claim-Evidence-Reasoning (CER) that supports YOUR claim. Is the mystery stone in the ring a diamond or not? Mystery Stone
Color: Colorless
Hardness: 8.5
Density: 5.92g/cm3
Melting Point: 2759 Degrees

Real Diamond
Color: Colorless
Hardness: 10.0
Density: 3.52g/cm3
Melting Point: 3547 Degrees C

Not a diamond.

Explanation:

Since there's too much of a difference in this case it's possible that the mystery stone can be another precious stone but not diamond.

"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"

alkaline metals are lithium, sodium, rubidium, potassium, cesium and francium.

alkali metals have electronegativity from 0.7 to 1, lowest in periodic table of elements, which means that alkali metals (i group in periodic table) has positive oxidation number in compounds.

electronegativity is a chemical property that describes the tendency of an atom to attract a shared pair of electrons towards itself.

alkaline metals (far left in main group) have lowest ionizations energy and easy remove valence electrons,

for example, potassium is the alkali metal and has a single valence electron in the outer electron shell.

electron configuration of potassium is: ₁₉k 1s²2s²2p⁶3s²3p⁶4s¹.

they can not exist alone in nature, because they are very reactive.