STRAIGHTERLINE CHEMISTRY FINAL EXAM

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STRAIGHTERLINE CHEMISTRY FINAL EXAM

LATEST – / 450 ACTUAL EXAM

QUESTIONS AND CORRECT VERIFIED

ANSWERS/ ALREADY GRADED A+

If 40.0 mL of H2SO4 solution reacts with 0.212 g of Na2CO3, what is the M molarity of the H2SO4 solution?Na2CO3 + H2SO4 Na2SO4 + CO2 + H2O

A. 0.50 M

B. 0.10 M

C. 0.20 M

D. 0.40 M

E. 0.050 M

Answer: E

What volume of 0.122 M HCl would react with 26.2 mL of 0.176 M NaOH?

• 37.8 mL
• 18.2 mL
• 5.56 mL
• 26.3 mL
• 75.6 mL

Answer: A

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pg. 2 What is the oxidation number of N in NaNO3?

• +1
• +2
• +3
• +4
• +5

Answer: E

In the following reaction, which species is being reduced?M FeBr3 + 3Cl2 2FeCl3 + 3Br2

• the Cl in Cl2
• the Fe in FeBr3
• the Br in FeBr3
• This is not a redox reaction.

Answer: A

Which is the oxidation number of arsenic in K3AsO4?

• +2
• +3
• +4
• +5
• +6

Answer: D

An endothermic reaction causes the surroundings to:

• warm up
• become acidic 2 / 4

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• condense
• decrease in temperature
• release CO2 - Correct Answer - D

The specific heat of gold is 0.129 J/g•oC. What is the molar heat capacity of gold (unit is J/mol•oC)?

• 0.039 J/mol•oC
• 0.129 J/mol•oC
• 25.4 J/mol•oC
• 39.0 kJ/mol•oC
• 197 J/mol•oC - Correct Answer - C

When 0.7521 g of benzoic acid was burned in a calorimeter containing 1000 g of water, a temperature rise of 3.60oC was observed. What is the heat capacity of the bomb calorimeter, excluding water? The heat of combustion of benzoic acid is ─26.42 kJ/g.

• 15.87 kJ/oC
• 4.18 kJ/oC
• 5.52 kJ/oC
• 1.34 kJ/oC
• 752.1 kJ/oC - Correct Answer - D

Naphthalene combustion can be used to determine the heat capacity of a bomb calorimeter. The heat of combustion of naphthalene is 40.1 kJ/g. When 0.8210 g of naphthalene was combusted in a calorimeter containing 1000 g of water a temperature rise of 4.21oC was observed. What is the heat capacity of the bomb calorimeter excluding the water?

• 32.9 kJ/oC
• 7.8 kJ/oC
• 1.76 kJ/oC
• 1.76 kJ/oC
• 15.3 kJ/oC - Correct Answer - C 3 / 4

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Which of the following processes is endothermic?

• O2(g) + 2H2(g) 2H2O(g)
• H2O(g) H2O(l)
• 3O2(g) + 2CH3OH(g) 2CO2(g) + 2H2O(g)
• H2O(s) H2O(l) - Correct Answer - D

A 100 mL sample of 0.200 M aqueous hydrochloric acid is added to 100 mL of 0.200 M aqueous ammonia in a calorimeter whose heat capacity is 480 J K ─ 1. The following reaction occurs when the two solutions are mixed.HCl(aq) + NH3(aq) NH4Cl(aq) The temperature increase is 2.34oC. Calculate ΔH per mole of HCl neutralized.

• 154 kJ
• 44.5 kJ
• 22.5 kJ
• ─22.5 kJ
• ─56.2 kJ - Correct Answer - E

A 0.1326 g sample of magnesium was burned in an oxygen bomb calorimeter. The Htotal heat capacity of the calorimeter plus water was 5760 J/oC. If the temperature rise of the calorimeter with water was 0.570oC, calculate the enthalpy of combustion of magnesium.Mg(s) + 1/2O2(g) MgO(s)

• ─3280 kJ/mol
• ─24.8 kJ/mol
• 435 kJ/mol
• 106 kJ/mol
• ─602 kJ/mol - Correct Answer - E
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