[tex]\Large \text{1)}[/tex]
[tex]\textbf{Use the formula and substitute the values}[/tex]
[tex]\displaystyle 0.3\ mol/L = \frac{n \ mol}{10 \times 10^{-3}\ L}[/tex]
[tex]\textbf{Solve for the number of moles}[/tex]
[tex]n = 0.003\ mol[/tex]
[tex]\textbf{Calculate final volume }[/tex]
[tex]40+10=50\ mL[/tex]
[tex]\textbf{Number of moles remains same. Solve for concentration}[/tex]
[tex]\displaystyle C=\frac{0.003\ mol}{50 \times 10^{-3}\ L} =0.06\ mol/L[/tex]
[tex]\Large \text{2)}[/tex]
[tex]\displaystyle DF=\frac{V_f}{V_i}[/tex]
[tex]\displaystyle DF=\frac{50}{10}=5[/tex]
