Find the Gibbs free energy of mixing when 2 moles of ethanol is mixed with 5 moles of water at a temperature of 27 °C. The pressure of the system is kept constant. The two liquids form an ideal solution. A. -10.45 J B. 10.45 kJ C. -11.75 kJ D. 11.75 kJ E. -10.45 kJ

How many mg in 1.35 g ? Report your answer to 3 decimal places (examples 1.042, 0.050, 0.198, 3.000).

Consider a buffer solution that contains 0.55 M NH2CH2CO2H and 0.35 M NH2CH2CO2Na. pKa(NH2CH2CO2H)=9.88. a. Calculate its pH. b. Calculate the change in pH if 0.155 g of solid NaOH is added to 250 mL of this solution. c. If the acceptable buffer range of the solution is ±0.10 pH units, calculate how many moles of H3O+ can be neutralized by 250 mL of the initial buffer.

What is the concentration in % (w/v) of a solution prepared from 50.0 g NaCl and 2.5 L of water? A. 5.0 % B. 2.0 % O C. 0.020 % D. 0.050 % E. 0.50 %

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Count the significant digits in each of these measurements: number of measurement significant digits ? 82300. kg 0.005100 J - 3.0 x 10 -2 kJ/mol -1 3.1 x 10 mL

What is the concentration in % (w/w), of a solution prepared by mixing 50.0 g NaCl and 150.0 g water? A. 0.250 % B. 33.3 % C. 40.0 % D. 25.0 % E. 3.00 %

5

If 46.5 mol of an ideal gas occupies 95.5 L at 373 K, what is the pressure of the gas? pressure: I atm

You are asked by the pharmacist to add 45 mEq of Ca Gluconate in an IV bag of D5W 1000mL. You have a concentrated vial of Ca Gluconate 4.4 mEq/mL, 50 mL. How many mL of this concentrated vial needs to be added to the IV bag?