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What is the specific surface area of a porous material if 10 mL of nitrogen gas is adsorbed at 77 K and 1 atm and the resulting monolayer thickness is 2.5 nm? The cross-sectional area of a nitrogen molecule is 0.16 nm^2.

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To calculate the specific surface area of the porous material, we can use the Brunauer-Emmett-Teller  BET  theory, which relates the amount of gas adsorbed to the surface area of the adsorbent. In this case, we have the following information:- Volume of nitrogen gas adsorbed  V_ads  = 10 mL- Temperature  T  = 77 K- Pressure  P  = 1 atm- Monolayer thickness  t  = 2.5 nm- Cross-sectional area of a nitrogen molecule  A_N2  = 0.16 nm^2First, we need to convert the volume of nitrogen gas adsorbed to the number of moles  n_ads  using the ideal gas law:PV = nRTWhere:- P = pressure  1 atm - V = volume  10 mL = 0.01 L - n = number of moles- R = ideal gas constant  0.0821 L atm /  mol K  - T = temperature  77 K n_ads = PV / RTn_ads =  1 atm * 0.01 L  /  0.0821 L atm /  mol K  * 77 K n_ads  0.000159 molNow, we can calculate the total surface area  A_total  of the porous material covered by the nitrogen molecules:A_total = n_ads * A_N2 / tA_total =  0.000159 mol * 0.16 nm^2  / 2.5 nmA_total  1.02  10^-5 m^2Finally, we can calculate the specific surface area  SSA  of the porous material by dividing the total surface area by the mass of the adsorbent. However, we do not have the mass of the adsorbent in the given information. If the mass of the adsorbent is provided, the specific surface area can be calculated as follows:SSA = A_total / mass of adsorbent

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