Question

when equal masses of the following compounds undergoes complete combustion, which chemicals will produce the least co₂?
4-greatest
a. benzene, c₆h₆
2
b. glucose, c₆h₁₂o₆
3
c. cyclohexane, c₆h₁₂
1-least
d. methane, ch₄
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question 10
0/1 pt 5 19 details
given the following equation:
pb(no₃)₂ + 2ki → pbi₂ + 2kno₃
how many grams of pb(no₃) are required to produce 187.7 grams of kno₃?
g pb(no₃)₂
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question 11
0/1 pt 5 19 details
part 1 of 2
a. write the balanced equation, including phase symbols, for the reaction between hi and manganese (iii) hydroxide.
+ → +

Explanation:

Step1: Find molar mass of \(KNO_3\) and \(Pb(NO_3)_2\)

Molar mass of \(KNO_3\): \(K(39.10) + N(14.01) + 3O(16.00) = 39.10 + 14.01 + 48.00 = 101.11\space g/mol\)
Molar mass of \(Pb(NO_3)_2\): \(Pb(207.2) + 2N(14.01) + 6O(16.00) = 207.2 + 28.02 + 96.00 = 331.22\space g/mol\)

Step2: Moles of \(KNO_3\)

Moles \(=\frac{mass}{molar\space mass}=\frac{187.7\space g}{101.11\space g/mol}\approx1.856\space mol\)

Step3: Mole ratio from equation

From \(Pb(NO_3)_2 + 2KI \to PbI_2 + 2KNO_3\), ratio \(Pb(NO_3)_2:KNO_3 = 1:2\).
Moles of \(Pb(NO_3)_2=\frac{1.856\space mol}{2}=0.928\space mol\)

Step4: Mass of \(Pb(NO_3)_2\)

Mass \(= moles \times molar\space mass = 0.928\space mol \times 331.22\space g/mol\approx307.4\space g\)

Answer:

\(307.4\) (or approximate value based on calculation precision)