1:

A piece of solid magnesium is reacted with hydrochloric acid toform hydrogen gas:

Mg_(s) + 2HCl_(aq) à MgCl_2(aq) + H_2(g)

What volume of hydrogen gas (in mL) is collected over water at25 °C by reaction of 0.450 g of Mg (AW = 24.3 g/mol) with 5.00 mLof 1.0 M HCl? The barometer records an atmospheric pressure of 762torr and the vapor pressure of water at this temperature is 23.35torr.

2:

Given the following balanced chemical reactions and theirenthalpies, calculate the enthalpy of reaction for 2C(s) +H₂(g) ---> C₂H₂(g):

C2H2(g) + (5/2) O2(g) ---> 2CO2(g) + H2O(ℓ)	ΔH° = -1299.5 kJ
C(s) + O2(g) ---> CO2(g)	ΔH° = -393.5 kJ
H2(g) + (1/2) O2(g) --->H2O(ℓ)	ΔH° = -285.8 kJ

3:

A 10.00 mL aliquot of 0.100 M NaOH is added to 15.00 mL of 0.100M HCl (don't try this at home, since acids and bases reactviolently to produce water and heat!) in a coffee cup calorimeter.The initial temperature of the two dilute liquids were both 25.0 ºCand the final temperature of the mixture was found tobe     37.8 ºC. What is the (molar) heat ofreaction for the neutralization?

4:

The heat of vaporization for toluene is 38.06 kJ/mol and thenormal boiling point is 111 ºC. Using the Clausius-Clapeyronequation, calculate the vapor pressure of toluene at roomtemperature (25 ºC).

5:

What is the equilibrium constant for a weak acid HA thatdissociates 1% at an initial concentration of 0.05 M according tothe following balanced chemical equation?

HA_(aq) ↔H⁺_(aq) + A^-_(aq)