Answer :
Answer:
2.6 M
Explanation:
We can use the dilution equation [tex]M_1V_1=M_2V_2[/tex] to calculate changes in either molarity or volume. The question tells us that the first solution has a molarity of 5 and a volume of 4.5L, which will be our respective [tex]M_1[/tex] an [tex]V_1[/tex] values. The second solution is known to have a volume of 8.7L, so that will be out [tex]V_2[/tex], in which we are only left to solve for [tex]M_2[/tex] by plugging in our known numbers:
[tex](5M)(4.5L)=M_2(8.7L)[/tex]
[tex]M_2=\frac{(5M)(4.5L)}{8.7L}[/tex]
[tex]M_2[/tex] ≈2.586 ≈ 2.6M (rounded to 2 significant figures, as that is the most given in the problem)
(We can check answers like these by multiplying both molarities with their corresponding volumes to see if the values equal each other. This conceptually makes sense, as multiplying molarity (moles divided by liters) by volume gives us moles, which should remain the same between dilutions)
