Answer:
+25°
Explanation:
The formula for calculatin the specific rotation, α, is:
α=αobs÷(c×l)
αobs being the rotation observed
c is being the concetration(g/mL)
l being the path length(dm)
So it ends up being:
α=+10°/(0.2 g/mL×2 dm)= +10°×ml/0,4g×dm
α=25°