Periodic Table
What subatomic particle determines the identity of an element?
Protons
What is the molecular shape of water?
bent
Balance (give coefficients in order):
C3H8 + O2 → CO2 + H2O
1,5,3,4
Is the following reaction exothermic or endothermic?
A + B + heat -> C
endothermic
What happens to a gas's volume if the temperature increases at constant pressure? (increase, decrease, stay the same)
volume increases
What is the difference between an Arrhenius base and a Bronsted Lowry Base
Arrehenius - OH donor
Bronted - proton acceptor
What is the name of the group 2 elements
What theory is used to predict molecular geometry
A student reacts 25.0 mols of aluminum with 12.0 mols of iron(III) oxide according to the thermite reaction:
2Al + Fe₂O₃ → 2Fe + Al₂O₃
Determine the limiting reactant.
iron(III) oxide limits
Convert 14oF to K
263 K
How does increasing temperature affect gas density at constant pressure?
density decreases
Which of these is a weak acid:
HCl, HNO3, H2SO4, HF
HF
Why does the atomic radius generally decrease from left to right across the periodic table?
An increasing number of protons pulls the electrons closer to the nucleus.
How many bonding pairs and lone pairs are in NH3, and what is its molecular shape?
3 bonding pairs, 1 lone pair, trigonal pyramidal
The theoretical yield of a reaction is 12.5 g of Cu, but only 9.40 g is collected.
Calculate the percent yield.
75%
C2H6 (g)+ 7/2 O2 (g)→ 2 CO2 (g)+ 3 H2O (g)
ΔH = -1560 kJ
C2H4 (g)+ 3 O2 (g)→ 2 CO2 (g)+ 2 H2O (g)
ΔH = -1411 kJ
H2 (g)+ 1/2 O2 (g) → H2O (g)
ΔH = -286 kJ
C2H6 (g)→ C2H4 (g) + H2 (g)
ΔH =
137 kJ
Calculate pressure: n = 1.50 mol, V = 10.0 L, T = 300 K
3.69 atm
The concentration of hydroxide for a base is 5.40x10-4. What is the pH for the solution?
10.7
How many protons, neutrons, and electrons does the following isotope have?
Neutral Uranium - 238
protons - 92
neutrons - 146
electrons - 92
Why is CO2 non-polar, even though the electronegativity difference between carbon and oxygen should be polar
the molecule is linear so the dipoles cancel
Predict the products of this double replacement reaction and balance:
BaCl₂ + Na₃PO₄ → ?
3BaCl₂ + 2Na₃PO₄ →Ba3(PO₄)2 + 6NaCl
At equilibrium, the concentrations are as follows: [HCl] = 0.97 M; [H3O+] = 2.3 M; [Cl-] = 4.2 M for the reaction
HCl (aq) + H2O (l)-> H3O+ (aq) + Cl- (aq)
What is Ka
9.95
A gas originally existed in a 1652 mL tank at STP. It is pumped into a much smaller tank (534 mL) where the new temperature was found to be 451 oC. What is the new pressure?
8.20 atms
Show the reaction for the neutralization of HBr in a buffer solution of carbonic acid (H2CO3) and sodium bicarbonate (NaHCO3)
HBr + NaHCO3 -> NaBr + H2CO3
Which element has the highest ionization energy but the lowest electronegativity
Helium
What is the molecular geometry and bond angles of XeF4?
square planar, bond angles are 90 and 180
A decomposition reaction occurs:
HgO →
If 18.0 g of HgO decomposes completely, calculate the mass of the diatomic product produced
1.33 g O2
The following reaction had initial concentrations of [H2] = 3.7 M, [I2] = 4.1 M [HI] = 0.00 M.
H2 (g) + I2 (g) -> 2 HI (g)
At equilibrium, [HI] = 3.4 M, find the equilibrium concentrations of [H2] and [I2]
[H2] = 2.0
[I2] = 2.4
In a 5682 mL container, there is 56.2 g of CO2, 44.5g N2, and 17.0 g H2 at 452 K. What is the total pressure in the container
73.7 atms
HCl has an initial concentration of 0.25 M. After being placed in water and going to equilibrium, the [H3O+] is found to be 0.062 M. Find the pH of the solution
1.2