Answer: The correct answer is option B i.e., 2.78 mol
Explanation:
Aluminium reacts with iodine to form Aluminium iodide

From the equation, it is clear that 3 moles of iodine reacts with 2 moles of Aluminium to form Aluminium iodide
We know
For 2 moles of Aluminium, 
3 moles of Iodine reacts with 54 g of Aluminium
? moles of iodine react with 50 g of Aluminium
For example, certain medications may influence the results of the test.
Drug test can show the presence of illicit or prescription drugs on hair samples, although the person has not used these drugs.
Some of false positive drug use is because of this medications: antihistamines, decongestants, antibiotics, antidepressants, analgesics and antipsychotics.
4.22 grams.
1. First find out how much AgNO3 weighs with one mole (107.87 g Ag + 14.007 g N + 48 g O = 169.89 grams)
2. Find the percent of Ag you have. So, (107.87 g/mol Ag)/(169.89 g/mol AgNO3)= 0.63 * 100 = 63%.
3. If you have 6.7 grams total, you know 63% of it is going to be silver, so just multiply 6.7 grams by .63 and you get 4.22 g Ag
Answer:
83°C
Explanation:
The following were obtained from the question:
M = 40g
C = 4.2J/g°C
T1 = 91°C
T2 =?
Q = 1300J
Q = MCΔT
ΔT = Q/CM
ΔT = 1300/(4.2x40)
ΔT = 8°C
But ΔT = T1 — T2 (since the reaction involves cooling)
ΔT = T1 — T2
8 = 91 — T2
Collect like terms
8 — 91 = —T2
— 83 = —T2
Multiply through by —1
T2 = 83°C
The final temperature is 83°C