If 450 mL of 6.0 M KBr solution is diluted to 900 mL, what is the concentration of the KBr solution?

1 Answer
Dec 18, 2015

Answer:

The concentration of the diluted KBr solution is 3 M.

Explanation:

Use the dilution equation #M_1V_1=M_2V_2#, where #M# is molarity in mol/L, and #V# is volume in liters.

Given/Known
#M_1="6.0 M"="6.0 mol/L"#
#V_1=450cancel"mL"xx(1"L")/(1000cancel"mL")="0.45 L"#
#V_2=900cancel"mL"xx(1"L")/(1000cancel"mL")="0.9 L"#

Unknown
#M_2#

Solution
Rearrange the dilution equation to isolate #M_2# and solve.
#M_1V_1=M_2V_2#

#M_2=(M_1V_1)/(V_2)#

#M_2=(6.0"mol"/"L"xx0.45cancel"L")/((0.9cancel"L"))="3 mol/L"="3 M"#