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When a gas condenses, it releases heat to its surroundings.  This is a(n)                             process.

Explain the difference between a saturated solution and a concentrated solution. 

Identify the BrØnsted base in this reaction.  H2O (l) + HNO3 (aq)  –>  H3O+ (aq)  + NO3- (aq)

Write  1) complete Ionic equation ( 4pts)  and 2) net ionic equation ( 4pts)  for this neutralization reaction: H2SO4 (aq)  + 2KOH(aq) –> K2SO4(aq)  + 2H2O(l)   All work must be shown for credit. No work=no credit. All work must in your own hand-writing.  

Ozone has the formula O3.  Which statement is correct concerning ozone?

The following 4 Essay questions require you to submit your work.  All work must be in your own handwriting.  The use of electronic devices, including writing tablets is not allowed.  No work= No credit.  Work must be neat and legible. If I cannot read it, you will not receive credit for it.  

A 25.0 mL sample of HBr is neutralized by reaction with 20.0 mL of 3.00 M KOH.  What is the concentration of HBr is the unknown sample? *hint- find the concentration of the base first. The answer must have the correct significant figures ( 1 pt) and unit ( 1 point) . Circle your final answer.  All work must be shown for credit. No work=no credit. All work must in your own hand-writing.  

The mixture of gas and air inside a cylinder reacts, releasing 400 kJ of total energy.  If the system does 250 kJ of work on the piston, how much energy is released as heat? 

A chemist prepares an aqueous solution of sodium hydroxide.  The solution contains 263.3 g of NaOH and has a volume of 750.0mL.  What is the molarity (moles/liter) of this solution? M=mols/L Answer with correct unit (1 point) and correct significant figures ( 1 point) All work must be shown for credit. No work=no credit. All work must in your own hand-writing.  

What is the formal charge on the oxygen atom in: CH3O   (Hint: Draw out the molecule with the correct valence electrons)