Acids and Bases
Describe an acid according to the Lewis definition
A molecule that accepts a pair of electrons
What is Chemical Equilibrium?
Reactants form products as fast as products form reactants
Which is stronger, Hydrogen bonding or Dispersion force?
Hydrogen Bonding
? P + ? HNO3 + ? H2O → ? H3PO4 + ? NO
3, 5, 2, 3, 5
How do ions effect the boiling temperature of water?
Which is not a potential Lewis Base?
1) NH3
2) H2O
3) CH4
4) CN-
3) CH4
Has no lone pair of electrons, or even electrons in general, to donate to an acid.
In AB + CD --> CB + AD + heat, which concentrations will increase when heat is added?
AB and CD
The density of a gas is 1.96 g·L-1 at 1.00 atm and 0 °C. What is the density of this gas at 0.855 atm and 25.0 C?
1.54
? Cr2O3 + ? KOH +? O2 → ? K2CrO4 + ? H2O
2, 8, 3, 4, 4
How does a catalyst affect chemical concentrations?
It doesn't
Which hydrated metal ion is most acidic under conditions of equal molar concentration in water?
(A) Al3+ (B) Ba2+ (C) K+ (D) Zn2+ (E) Ag+
(A) Al3+
Its small size as well as its high charge makes it very easy for the ion to detach a hydrogen from a water molecule
Given that 2X(g) + Y(g) --> 2Z(g) ∆H = –335 kJ, you will need ______ heat and _______ pressure to get the most concentration of Z possible.
(More/Less)
Less, More
Since the reaction is exothermic, less heat produces more product.
Since there are 3 moles on the reactant side and only 2 on the product side, more pressure will produce more product.
A 1200 mL sample of helium gas is at a pressure of 350 mmHg and a temperature of 300 K. What volume will this gas sample occupy if the pressure is increased to 700 mmHg and the temperature is increased to 400 K?
800mL
P*V/T=P*V/T
Why is the following incorrect? Mg3 + N2 → Mg3N2
Mg does not exist as Mg3, since it cannot react with itself. The correct reaction is:
3Mg + N2 → Mg3N2
What lowers the activation energy of a reaction?
A catalyst
Which of these is NOT a Lewis Acid-Base Reaction?
1) Cu2+ (aq) + 4NH3 (aq) --> [Cu(NH3)4]2+ (aq)
2) HCl(g) + NH3 (g) --> NH4Cl (s)
3) H+ + OH- --> H2O
4) 2Na (s) + Cl2 (g) --> 2NaCl (s)
4) 2Na (s) + Cl2 (g) --> 2NaCl (s)
There is no base with a lone pair, so this cannot be classified as a Lewis Acid-Base Reaction.
How much catalyst do you need (in grams) to produce more Ammonium in this solution?
N2 + 3H2 --> 2NH3 ∆H = –92 kJ
112g N2
82g H2
None, a catalyst will not produce extra product
A sample of nitrogen at pressure P is contained in a sealed syringe with a movable piston. If the volume of the sample were doubled and the absolute temperature tripled, the new pressure of the gas would be ______ times the original.
1.5
2P x 2V/2T = XP x 4V/6T
X = 3
2 x 1.5 = 3
Which is the strongest oxidizing agent?
Na → Na+ + e– 2.71 V
Cd → Cd2+ + 2e– 0.40 V
H2 → 2H+ + 2e– 0.00 V
Ag → Ag+ + e– –0.80 V
Na
The higher the voltage, the more likely it is to be reduced
Does a catalyst make a reaction more or less exothermic?
No effect
Which element in Group 5A forms the most basic oxide?
(A) N (B) P (C) As (D) Sb (E) Bi
(E) Bi
Bismuth is the only metal of the group, so it will be the only basic oxide
Chemical Equilibrium is ___________ reaction rate.
(Dependent upon, independent of, inverse to)
Independent of
Who is Big Al?
What does isoelectronic mean?
The same number of electrons.
A catalyst lowers the activation energy of a reaction by...
Providing an alternate route for a chemical reaction to take place