Basic Chemistry: 1405 Fall 2012, Oct 25, 2012. Due Oct 29, 2012, No late hand ins accepted
Answer all questions. Total Score 50
1.The pressure of a gas sample was measured to be 654 mmHg. What is the pressure in kPa? (1
atm = 1.01325 × 105 Pa)
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(Hint: Remember 1 atomsphere is = 760mm Hg)
2.The following reaction was carried out in water as a solvent.
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a. Write the products of this reaction indicating their status and balance this equation
Na3PO4 (aq) + Ca(NO3)2 (aq)
b. How would you label this reaction, as a displacement, acid-base or a metathesis reaction?
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c. How much Na3PO4 is required to react with 3g of Ca(NO3)2, ?
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3. What is the definition of acid and a base. Give an example for each. 2X2
III Using the following reagents above, write the equation for: 1
A. a reaction between a strong base and a strong acid:
B. Calculate the number of moles in 5 g of CH3COOH and 10g of NaOH
4.In the oxidation and reduction reaction below,
answers right!)
MnO4– + 5H2SO3
2X2
2Mn2+ + 5SO4 2– + 4H+ + 3H2O
( 2 bonus points for getting the
Hint: What are the two major atoms involved in the reaction here, Mn and S. Calculate their valencies
on the LHS and RHS and you will get the answer to both these questions:
a. Identify the oxidizing and reducing agents in the following chemical reaction.
b. Indicate the change in oxidation states of the oxidizing and reducing agent:
5. Define what is the metal activity series?
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Predict if the following reactions will take place or not:
a.Zn(s) + CoCl2(aq)
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b.Ni(s) + Cu(NO3)2(aq)
c.CuSO4 + Fe
d.Na + AgNO3
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e.MgCl2 + Al
6. a. A sample of a gas occupies 1.40 × 103 mL at 25°C and 760 mmHg. What volume will it occupy
at the same temperature and 380 mmHg?
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b. Indicate the relationship underlying the equation for this calculation:
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7. Calculate the number of moles of gas contained in a 10.0 L tank at 22°C and 105 atm. (R=
0.08206 L×atm/K×mol): Hint: remember to check the units 3
8. A combustion reaction is an example of the burning of any compound completely in air. Indicate
which of the following examples are combustion reaction: 4
A. 2C2H2 (g) + 7O2(g)
4CO2 (g) + 6H2O(l)
B) LiOH(aq) + HNO3(aq)
LiNO3(aq) + H2O(l)
C) N2(g) + 2O2(g)
2NO2(g)
D) CO(g) + O 2(g)
CO2(g)
9. Determine the molar mass of chloroform gas if a sample weighing 0.389 g is collected in a flask
with a volume of 102 cm3 at 97°C. The pressure of the chloroform is 728 mmHg.
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Hint: n, the number of moles =mass / MW
PV=nRT.
Use the following two equations to solve for the above. Check for conversion factors and unit and
use the correct R value.
10. Define the terms solution, solute, and solvent.
11a.Define Dalton’s law of partial pressure.
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b. If I have a container of 3L containing air, predict how you would calculate the total pressure of
this mixture of gases based on Dalton’s law:
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Hint: use the most abundant 4 gases found in air.