Chapter 6
How many H atoms are in 2.3 moles of NH3?
4.2×1024
Consider the following reaction: 2 H2O2(l) → 2 H2O(l) + O2(g)
The heat of the reaction is -196 kJ. Which of the following statements is true about this reaction?
A) The reaction is endothermic and heat is absorbed in this reaction.
B) The reaction is exothermic and heat is released by this reaction.
C) The reaction is endothermic and heat is neither released nor absorbed by this reaction.
D) The reaction is exothermic and heat is absorbed in this reaction.
E) The reaction is endothermic and heat is released by this reaction.
B) The reaction is exothermic and heat is released by this reaction.
What is the pressure (in atm) of 0.063 moles of CH4 gas found in a 900 mL container at a temperature of -12.00 °C?
A) 2.50 atm
B) 1.2 atm
C) 0.56 atm
D) 0.38 atm
E) 1.5 atm
E) 1.5 atm
What is the electron and molecular geometry of NH₃?
tetrahedral, trigonal pyramidal
Calcium oxide reacts with water in a combination reaction to produce calcium hydroxide. In a particular experiment, a 4.50 g sample of CaO is reacted with excess water and 4.50 g of Ca(OH)2 is recovered. What is the percent yield in this experiment? (Note: the molar mass of CaO is 56.08 g/mol, H2O is 18.01 g/mol, and Ca(OH)2 is 74.09 g/mol.
CaO (s) + H2O (l) → Ca(OH)2 ₍ₛ₎
75.7%
A quantity of Ne gas that was originally held at 0.667 atm pressure in a 1.50 L container at -80.0 °C is transferred to a 2.50 L container at 200.0 °C. What is the pressure (in atm) of Ne in the new container ?
A) 0.372 atm
B) 3.80 atm
C) 0.980 atm
D) 1.35 atm
E) 5.56 atm
C) 0.980 atm
What is the predicted bond angle for BeCl2?
180
When 10.0 g of Al reacts with 20.0 g of O₂: 4Al(s)+3O2(g)→2Al2O3(s)
what is the limiting reactant?
Al
At a constant temperature of 250 K, 1.404 moles of a N2 gas exerts a pressure of 1.0 atm
and has a volume of 0.25 L. What is the volume of N2 gas if there are only 0.750 moles of it at
the same pressure ?
A) 0.47 L
B) 0.13 L
C) 2.3 L
D) 0.15 L
E) 1.4 L
B) 0.13 L
Consider the following molecules:
Rank the molecules in order of increasing boiling point (lowest → highest).
CH₄ < CH₃Cl < CH₃OH < CH₃CH₂OH
1 < 3 < 2 < 4
What mass of NH3 is needed to completely react with 0.600 moles of O2 (g) based on the reaction below?
4NH3 (g) + 3O2 (g) → 2N2 (g) + 6H2O (g)
13.6 g NH3
If the pressure of a constant amount of gas at constant volume is decreased by a factor of 2, what happens to its temperature?
A) The temperature increases by a factor of 2.
B) The temperature will not change.
C) The temperature decreases by a factor of 2.
D) The temperature increases by a factor of 4.
E) The temperature decreases by a factor of 4.
C) The temperature decreases by a factor of 2.