Answer:
0.12 M
Explanation:
To find the new concentration, you need to (1) find the moles of Solution A (via the molarity equation), then (2) find the moles of Solution B, then (3) combine all of the moles and volumes, and then (4) calculate the new molarity. The final answer should have 2 sig figs to reflect the lowest amount of sig figs in the given values.
<u>Solution A:</u>
7.7 mL / 1,000 = 0.0077 L
Molarity = moles / volume
0.10 M = moles / 0.0077 L
0.00077 = moles
<u>Solution B:</u>
18.3 mL / 1,000 = 0.0183 L
Molarity = moles / volume
0.20 M = moles / 0.0183 L
0.00366 = moles
<u>New Solution:</u>
11.7 mL / 1,000 = 0.0117 L
New Volume = 0.0077 L + 0.0183 L + 0.0117 L
New Volume = 0.0377 L
New Moles = 0.00077 moles + 0.00366 moles
New Moles = 0.00443 moles
Molarity = moles / volume
Molarity = 0.0043 moles / 0.0377 L
Molarity = 0.1175 M = 0.12 M