Answer:1 mol of Mg(NO3)2 contains 6.022*10^23 molecules
3 mol Mg(NO3)2 contains 3*6.022*10^23 = 1.81*10^24 molecules
Each Mg(NO3)2 molecule contains 2 N atoms
Number of N atoms = 2*1.81*10^24 = 3.62*10^24 N atoms.
Answer:
The interaction reaction of calcium oxide and water leads to the formation of calcium hydroxide, this reaction is exothermic, which indicates that energy is released.
CaO(s) + H2O ⇒ Ca(OH)2
Explanation:
Calcium oxide reacts violently with water, causing it to reach 90 C. It then forms calcium hydroxide, also called slaked lime. It is heated because it releases energy in the form of heat, because the new substance formed (slaked lime) has less internal energy than the original and this is released in the form of heat. As a general rule, acid and base solutions are exothermic.
<span>The atoms of a chemical element can exist in different types. These are calledisotopes. They have the same number of protons (and electrons), but different numbers of neutrons.</span>
Answer:
A. Generally ionic compounds are formed metal and non metal elements since they forms opposite charged ions due to difference in their Electronegativity values.
NaCl, MgCl2, Ca(OH)2 etc are ionic compounds.
B. Generally transition elements (D elements) forms cations with different charges or simply they exist in different oxidation states due to availability of empty d orbitals.
Examples are Iron exsits as Fe+2 and Fe+3
Mn exists as Mn+2 , Mn+4, Mn+6 ,Mn+7 etc.
