30 points

you have a 7.00-liter container with 1.88 x10^23 molecules of methane gas, ch4, at stp. how many molecules of nitrogen gas, n2, are in an identical container at the same temperature and pressure?

2.00 x1023
2.00 x1024
1.88 x1023
1.80 x1024

1.88x10²³ molecules of N₂

Explanation:

If the N₂ is at STP conditions and occupies 7L of volume, like the CH₄ we can apply the Ideal Gases Law to find out the moles.

STP = 273K (temperature) and 1atm (pressure)

P .V = n .R.T

1atm . 7L = n . 0.082L.atm/mol.K . 273K

(1atm . 7L) / (0.082L.atm/mol.K . 273K) = n

0.312 moles = n

These are the moles of N₂, so how many molecules are on it?

1 mol has NA molecules

0.312 moles have ( 0.312 .NA) = 1.88x10²³

NA  = Avogadro's number (6.02x10²³)

he uptake of drugs from the intestine is often strongly influenced by diffusion. for example, consider a water-insoluble steroid for treating inflammation that is solubilized in aggregates of detergent molecules, called micelles. these micelles, aggregates of 80 soap molecules, have a molecular weight of 24,000, a diameter of 2.6 nm, and a charge of -27. the positively charge ions (counterions) in this system are na".