It is B, and also for a moment I didn't understand that 4.69 x 10^22. I almost did this whole problem wrong.
Answer:
Earth's gravity is strong enough to hold onto its atmosphere and keep it from drifting into space.
Answer:
The osmotic pressure of cell is 
KPa
Explanation:
As we know the osmotic pressure is equal to
Where
i is the Van Hoff factor
c is the concentration of solution
R is the ideal gas constant
and T is the temperature.
Substituting the given values, we get -
KPa
Answer:
223 g O₂
Explanation:
To find the mass of oxygen gas needed, you need to (1) convert moles Al to moles O₂ (via the mole-to-mole ratio from reaction coefficients) and then (2) convert moles O₂ to grams O₂ (via the molar mass). When writing your ratios/conversions, the desired unit should be in the numerator in order to allow for the cancellation of the previous unit. The final answer should have 3 sig figs because the given value (9.30 moles) has 3 sig figs.
4 Al + 3 O₂ ----> 2 Al₂O₃
^ ^
Molar Mass (O₂): 32.0 g/mol
9.3 moles Al 3 moles O₂ 32.0 g
------------------- x --------------------- x -------------------- = 223 g O₂
4 moles Al 1 mole
