Chem calculations 1LB Final

It took 32.47 mL of 0.1224 M NaOH to reach the endpoint when titrating a sample containing 0.4073 g of an unknown acid. How many moles of sodium hydroxide were used?

0.00397 mol NaOh

It took 32.47 mL of 0.1224 M NaOH to reach the endpoint when titrating a sample containing 0.6567 g of an unknown monoprotic acid. What is the molar mass of this acid? You must show all calculations to receive credit.,

165 g/mol

A solid 0.1595-g sample of aluminum generated by the reaction with hydrochloric acid displaces and collects 106.8 mL of hydrogen gas. The barometric pressure is 733.2 mmHg, and the room temperature is 21.3°C. If water vapor pressure at 21.3°C is 18.7 mmHg, and the molar volume of gas is calculated using the Ideal Gas Law, what is n (mol H₂)?,

4.16×10^-3 mol H₂

To a calorimeter containing 50.0 g water at 25.0 °C, 25.0 g of aluminum metal (initially heated to 100.0 °C) is added. Assuming negligible heat loss to the calorimeter or the surroundings, what is the final temperature of the system? (cwater = 4.18 J/g°C, cAl = 0.895 J/g°C),

32.2 °C

What is the molality of a solution prepared by dissolving 1.87g of HCl (molar mass = 36.46 g/mol) in 237g of H₂O?

0.215 mol/kg or M

A student measured the vapor pressure of 1.0 molal solutions of a nonvolatile solute at various temperatures. She then used the data to graph ln(P) vs 1/T. The slope of the best straight line was -2500 K. Calculate ΔHvap in units of J/mol. (R = 8.314 J/mol·K),

20,785 J/mol

What is the molarity of I⁻ after mixing 15 mL of 0.015 M solution with another solution to a total volume of 50 mL?

0.0045M

What is the freezing point depression (ΔTf\Delta T_fΔTf​) if the solution freezes at –6.90°C?

6.9 degrees celsius

What is the molality of a solution that depresses the freezing point by 6.90°C if Kf=1.86∘C

3.71 Mol/kg

A solution is made by dissolving 62.00 g of an unknown in water and yields 0.4637 mol (based on molality). What is the molar mass of the unknown?

133.7g