Answer:
[∝] = +472
Explanation:
Specific rotation in a solution is defined as:
[∝] = ∝ / c×l
Where:
[∝] is specific rotation, ∝ is observed rotation (In degrees), c is concentration in g/mL and l is path length (In dm).
∝: +47.2°
c: 2.0g / 50mL = 0.04g/mL
l: 25cm × (1dm /10cm) = 2.5dm
Replacing:
[∝] = +47.2° / 0.04g/mL×2.5dm = <em>+472</em>
I hope it helps!
Answer: 0.3794 moles of Iodine gas are produced.
Explanation:
Volume of iodine gas produced at STP =8.5 L
At STP, the 1 mol of gas occupies volume = 22.4 L
So, 8.5 L of volume will be occupied by:
0.3794 moles of Iodine gas are produced.
Answer:
half-life = 3.8 days
total time of decay = 15.2 days
initial amount = 100. g
number of half-lives past: 15.2/3.8 = 4 half-lives
4 half-lives = 1/16 remains
100. g x 1/16 = 6.25 g
The amount of sample that is left after a certain period of time, given the half-life, h, can be calculated through the equation.
A(t) = A(o) (1/2)^(t/d)
where t is the certain period of time. Substituting the known values,
A(t) = (20 mg)(1/2)^(85.80/14.30)
Solving,
A(t) = 0.3125 mg
Hence, the answer is 0.3125 mg.
