The absolute value of the difference in electronegativity (ΔEN) of two bonded atoms provides a rough measure of the polarity to be expected in the bond and, thus, the bond type. When the difference is very small or zero, the bond is covalent and nonpolar. When it is large, the bond is polar covalent or ionic.
 
        
             
        
        
        
Iron is a type of element because iron is metal and metal is also a mineral
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Answer:
0.252 milimoles
Explanation:
To convert mass of a substance to moles it is necessary to use the molar mass of the substance.
The formula of morphine is C₁₇H₁₉NO₃, thus, its molar mass is:
C: 17*12.01g/mol = 204.17g/mol
H: 19*1.01g/mol = 19.19g/mol
N: 1*14g/mol = 14g/mol
O: 3*16g/mol = 48g/mol.
204.17 + 19.19 + 14 + 16 = <em>285.36g/mol</em>
Thus, moles of 71.891 mg = 0.071891g:
0.071891g × (1mol / 285.36g) = 2.5193x10⁻⁴ moles
As 1 mole = 1000 milimoles:
2.5193x10⁻⁴ moles = <em>0.252 milimoles</em>
 
        
             
        
        
        
Answer:
6 C(s) +  3 O₂(g) + 2 Fe₂O₃(s) →  4 Fe(s) + 6 CO₂(g)
Explanation:
Iron can be formed in two steps.
Step 1: 2 C(s) + O₂(g) → 2 CO(g)
Step 2: Fe₂O₃(s) + 3 CO(g) → 2 Fe(s) + 3 CO₂(g)
In order to get the net chemical equation, we will multiply the first step by 3, the second step by 2, and then add them.
6 C(s) +  3 O₂(g) → 6 CO(g)
+
2 Fe₂O₃(s) + 6 CO(g) → 4 Fe(s) + 6 CO₂(g)
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6 C(s) +  3 O₂(g) + 2 Fe₂O₃(s) + 6 CO(g) → 6 CO(g) + 4 Fe(s) + 6 CO₂(g)
6 C(s) +  3 O₂(g) + 2 Fe₂O₃(s) →  4 Fe(s) + 6 CO₂(g)