<h3>
Answer:</h3>
1.497 mol Ir
<h3>
General Formulas and Concepts:</h3>
<u>Math</u>
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
<u>Chemistry</u>
<u>Atomic Structure</u>
<u>Stoichiometry</u>
- Using Dimensional Analysis
<h3>
Explanation:</h3>
<u>Step 1: Define</u>
287.7 g Ir
<u>Step 2: Identify Conversions</u>
[PT] Molar Mass of Ir - 192.22 g/mol
<u>Step 3: Convert</u>
- Set up:

- Multiply/Divide:

<u>Step 4: Check</u>
<em>Follow sig fig rules and round. We are given 4 sig figs.</em>
1.49672 mol Ir ≈ 1.497 mol Ir
Answer:
(a) Ionic
(b) Nonpolar covalent
(c) Polar covalent
(d) Polar covalent
(e) Nonpolar covalent
(f) Polar covalent
<em>For those substances with polar covalent bonds, which has the least polar bond?</em> NO₂
<em>For those substances with polar covalent bonds, which has the most polar bond?</em> BF₃
Explanation:
<em>Are the bonds in each of the following substances ionic, nonpolar covalent, or polar covalent?</em>
The nature of a bond depends on the modulus of the difference of electronegativity (|ΔEN|) between the atoms that form it.
- If |ΔEN| = 0, the bond is nonpolar covalent.
- If 0 < |ΔEN| ≤ 2, the bond is polar covalent.
- If |ΔEN| > 2, the bond is ionic.
<em>(a) KCl</em> |ΔEN| = |EN(K) - EN(Cl)| = |0.8 - 3.0| = 2.2. The bond is ionic.
<em>(b) P₄</em> |ΔEN| = |EN(P) - EN(P)| = |2.1 - 2.1| = 0.0. The bond is nonpolar covalent.
<em>(c) BF₃</em> |ΔEN| = |EN(B) - EN(F)| = |2.0 - 4.0| = 2.0. The bond is polar covalent.
<em>(d) SO₂</em> |ΔEN| = |EN(S) - EN(O)| = |2.5 - 3.5| = 1.0. The bond is polar covalent.
<em>(e) Br₂</em> |ΔEN| = |EN(Br) - EN(Br)| = |2.8 - 2.8| = 0.0. The bond is nonpolar covalent.
<em>(f) NO₂</em> |ΔEN| = |EN(N) - EN(O)| = |3.0 - 3.5| = 0.5. The bond is polar covalent.