Final answer:
To calculate the number of nitrogen monoxide molecules produced in the reaction, we need to use the stoichiometry of the balanced equation. From the given information of a 0.688 M HNO₃ solution with a volume of 15.0 mL, we can calculate the number of moles of HNO₃, and then use the mole ratio to calculate the number of moles of NO. Finally, we can convert the moles of NO to the number of nitrogen monoxide molecules using Avogadro's number.
Step-by-step explanation:
The balanced chemical equation given is:
3Cu(s)+8HNO₃(aq)→3Cu(NO₃)₂(aq)+2NO(g)+4H₂O(l)
To determine the number of nitrogen monoxide molecules produced, we can use the stoichiometry of the balanced equation. According to the equation, for every 3 moles of Cu(NO₃)₂ produced, 2 moles of NO are also produced. This means that the mole ratio of Cu(NO₃)₂ to NO is 3:2.
First, we need to calculate the number of moles of Cu(NO₃)₂ produced from the given information:
Volume of HNO₃ solution = 15.0 mL = 0.015 L
Concentration of HNO₃ solution = 0.688 M
Using the formula: moles = concentration x volume, we can calculate the number of moles of HNO₃:
moles of HNO₃ = 0.688 M x 0.015 L = 0.01032 moles
Since the mole ratio of Cu(NO₃)₂ to NO is 3:2, the number of moles of NO produced is:
moles of NO = (2/3) x 0.01032 moles = 0.00688 moles
Finally, we can calculate the number of nitrogen monoxide molecules produced by multiplying the number of moles of NO by Avogadro's number:
Number of NO molecules = 0.00688 moles x 6.022 x 10²³ molecules/mole = 4.14 x 10²¹ molecules