“<u>Aluminum</u>” and “<u>Nitrogen</u>” form an ionic bond.
Option: D
<u>Explanation</u>:
Aluminum and nitrogen are most likely to form an “ionic bond” among given pairs of elements in form of aluminum nitride. AlN is partially covalent and also show ionic characteristics as N needs 3 electrons to fill outer shell and Al has 3 electrons in valence shell. Hence 
is cation and 
is anion and have “electrostatic force” of attraction between these oppositely charged ions. Here ionic behavior is seen as nitrogen is more “electronegative” hence attract the shared pair of electrons which is earlier responsible for partial covalent bond formation.
Answer is: there is 1,368·10²⁵ atoms of carbon.
N(C₃H₈) = 4,56·10²⁴.
From molecular formula: in one molecule of propane there is three atoms of carbon:
N(C) = 3 · 4,56·10²⁴.
N(C) = 1,368·10²⁵.
Given data:
Mass of cesium chloride CsCl (m) = 52.3 g
Mass of water (mh2O)= 60.0 g
Volume of the solution (V) = 63.3 ml
Step 1: Calculate the number of moles of CsCl
Molar mass of CsCl = 168.36 g/mol
Mass of CsCl = 52.3 g
# moles = mass/molar mass = 52.3 g/168.36 g.mol-1 = 0.3106 moles
Step 2: Volume of solution in Liters
1000 ml = 1 liter
therefore, 63.3 ml corresponds to : 63.3 ml * 1 L/1000 ml = 0.0633 L
Step 3: Calculate molarity of CsCl
Molarity = moles of CsCl/volume of solution
= 0.3106 moles/0.0633 L = 4.91 moles/L
Molarity = 4.91 M
FeS is an example of an ionic compound as in the formula there is a metal of Fe iron chemically bonded to the nonmetal S sulphur. Resulting in a strong electrostatic attraction due to the transfer of valence electrons from the iron to the Sulphur.
