Chem Lab Exam Ch. 7-12 Questions and Correct Answers
7 views 0 purchase
Course
Chem
Institution
Chem
What parts are present in every chemical equation?
~ -At least one reactant
-At least one product
-An arrow
Identify the correct equation and net ionic equation for the reaction between aqueous
hydrochloric acid and aqueous sodium carbonate.
~ ~2HCl(aq)+Na2CO3(aq)⟶2NaCl(aq)+H2O(l)+CO2(g)
...
Chem Lab Exam Ch. 7-12 Questions
and Correct Answers
Which statement is true about a chemical reaction at equilibrium?
✓✓~ The forward reaction rate is equal to the reverse reaction rate.
Consider the two reactions of iron ions, one with thiocyanate (SCN−) ions and one
with chloride (Cl−) ions.
✓✓~ If you create an equilibrium mixture from Fe3+ and SCN− ions, adding Cl− ions will shift the
iron-thiocyanate equilibrium to the reactant side because it removes iron from the iron-thiocyanate
equilibrium mixture.
Determine whether each description corresponds to an endothermic reaction or an
exothermic reaction.
✓✓~ -Heat is a reactant in the reaction. (Endothermic)
-The reaction mixture feels cool from the outside. (Endothermic)
-The reaction mixture feels warm from the outside. (Exothermic)
-Heat is a product in the reaction. (Exothermic)
When any reversible reaction is at equilibrium, what conditions are necessarily true?
✓✓~ -Reactants and products are both present in the reaction mixture.
-The rate of the forward reaction equals the rate of the reverse reaction.
-The amounts of reactants and products has stopped changing.
, According to Le Châtelier's Principle, heat applied to an exothermic reaction will shift
the reaction towards _____________. Heat applied to an endothermic reaction will
shift the reaction towards _____________.
✓✓~ the reactants , the products
Consider the equilibrium system of cobalt complexes.
Co(H2O)62+(aq)+4Cl−(aq)−⇀↽−CoCl42−(aq)+6H2O(l)
The Co(H2O)62+(aq) complex is pink and the
CoCl42−(aq) complex is light blue.
Determine what each color observation means about changes made to the system at
equilibrium.
✓✓~ -The solution changes from light blue to pink. >>The change shifted the equilibrium to the
reactant side.
-The solution stays light blue after adding a chemical. >>The change did not shift the
equilibrium system.
-The solution changes from pink to light blue. >>The change shifted the equilibrium
to the product side.
A change in temperature can shift an equilibrium system.
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller Examify. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $9.99. You're not tied to anything after your purchase.