Answer:
1. 0.0637 moles of nitrogen.
2. The partial pressure of oxygen is 0.21 atm.
Explanation:
1. If we assume ideal behaviour, we can use the Law of ideal gases to find the moles of nitrogen, considering that air composition is mainly nitrogen (78%), oxygen (21%) and argon (1%):
2. Now, in order to find he partial pressure of oxygen we need to find the total moles of air, and then the moles of oxygen. Then, we use these results to determine the molar fraction of oxygen, to multiply it with total pressure and get the partial pressure of oxygen as follows:
As you see, the molar fraction and volume fraction are the same because of the assumption of ideal behaviour.
Answer:
Activating a glow stick is the example of a chemical change, as snapping one will cause a chemical reaction, causing the glow. All of the other options are physical changes because nothing new is formed. Hope this helps!
The correct answer is 0.06857 moles.
C₆H₁₂O₆, that is, glucose has six carbons, twelve hydrogens, and six oxygen atoms. The atomic weight of C, H and O are as follows:
Six atoms of carbon = 6 × 12.01 g = 72.06 g
Twelve atoms of hydrogen = 12 × 1.008 g = 12.096 g
Six atoms of oxygen = 6 × 16.00 g = 96.00 g
So, the molar mass of C₆H₁₂O₆ is 72.06 g + 12.096 g + 96.0 g = 180.156 g.
It can also be written in the form as 180.16 g of C₆H₁₂O₆ is equal to 1 mole of C₆H₁₂O₆or 180.16 g/mole (as the molar mass)
Now, there is a need to find moles of 12.354 grams of C₆H₁₂O₆. So, the final conversion is:
12.354 g C₆H₁₂O₆ × 1 mole of C₆H₁₂O₆ / 180.16 g C₆H₁₂O₆
= 0.06857 moles
