The answer is 3/4.
The coefficient next to each reactant represents the amount of moles. The compound for oxygen is O2 and the compound for aluminum is 4. We can see that the number next to O2 is 3 and the number next to aluminum is 4.
Answer:
Sodium Fluoride F 18 Injection is a positron emitting radiopharmaceutical, no-carrier added.
Explanation:
Element Name Fluorine
Element Symbol F
Atomic Number 9

Blank # 1 - keep safe distance from the burner
Blank # 2 - Place the equipments on the right place after use
Blank # 3 - perform experiments with proper lab equipment and safety tools
Blank # 4 - Don't break any test tube or lab equipment
(maybe it can be hazardous)
Answer: The partial pressure of the dry oxygen is 742 torr
Explanation:
Dalton's Law of Partial Pressure states that the total pressure exerted by a mixture of gases is the sum of partial pressure of each individual gas present. Thus 
Given; Total pressure = 762 torr
partial pressure of water = 19.8 torr
partial pressure of dry oxygen = ? torr
Total pressure = partial pressure of water + partial pressure of dry oxygen
762 torr = 19.8 torr = partial pressure of dry oxygen
partial pressure of dry oxygen = 742 torr
The partial pressure of the dry oxygen is 742 torr