Exam 1
Arrange the elements in order of increasing ionization energy: Te, Pb, Cl, S, Sn.
Pb < Sn < Te < S < Cl
Name/ write the formula for the following:
Lead (IV) Oxide
dinitrogen heptoxide
KClO3
CS2
PbO2
N2O7
potassium chlorate
carbon disulfide
At 137 degrees Celsius and under a pressure of 3.11 atm, a 276 g sample of an unknown noble gas occupies 13.46 L of space. What is the gas?
222.58 g/mol
RADON (Rn)
Determine electron and molecular geometry for Nitrite, is it polar?
Electron: trigonal planar
Molecular: Bent
Polar
a. 600 uL= ___ mL
b. 80 mg= ___ Mg
0.6 mL
8 x 10^-8 Mg
How much heat is needed to warm 250 g of water from 22 celsius to 98 celsius?
C=4.184 J/gC
7.9x 10^4
1.00 L of a solution is prepared by dissolving 125.6 g of NaF in it. If I took 180 mL of that solution and diluted it to 500 mL, determine the molarity of the resulting solution.
1.08 M
Write out the balanced single replacement reaction that occurs when you react aluminum with copper (II) sulfate
2 Al + 3 CuSO4 -> Al2(SO4)3 + 3 Cu
write the abbreviated electron configuration for each of the following:
a. Carbon
b. Antimony (Sb)
a. [He]2s2 2p2
b. [Kr]5s2 4d10 5p3
Write the nuclear reaction for the neutron-induced fission of U-235 to produce Ba-139 and Kr-94. How many neutrons are produced in the reaction?
2 neutrons
2NH3(g)-><- N2 (g) + 3 H2 (g)
At 500K, the following concentrations were measured:
[N2]= 3.0 x10^-2 M
[H2]= 3.7 x 10^-2 M
[NH3]= 1.6 x 10^-2 M
What is Kc?
5.9 x 10^-3
For the following endothermic reaction, which change would cause the equilibrium to shift to the right?
CH4 (g) + 2H2S (g) <- -> CS2 (g) + 4H2 (g)
a. decrease concentration of 2H2S
b. Increase pressure on the system
c. increase the temp of the system
d. increase the concentration of CS2
e. Decrease the concentration of methane (CH4)
c. Increase the temp of the system because a decrease in temp favors exothermic reactions.
what are the following number of protons, neutrons, and electrons in the following:
a. 89Sr
38
b. 52 Cr
24
a. p=38 n=51 e=38
b. p=24 n=28 e= 24
An element has a half-life of 35.5 years, how much of a 94.5g sample of the element will be left in 177.5 years?
2.95g
4NH3 + 5O2 -> 4NO + 6H2O
3.25 g of NH3 are allowed to react with 3.50g of O2
How much NO is formed in g and which is the limiting reactant?
2.63 g NO, O2 is the LR
For the reaction, calculate how many moles of product form when 1.75 mol of the reactant in italics react. Assume there is more than enough of the other reactant.
H2(g)+Cl2(g)→2 HCl(g)
3.50 mol of HCl
How much heat in kilojoules is evolved in converting 1.00 mol of steam at 145 °C to ice at –50.0 °C? The specific heat capacity of steam is 1.84 J/g °C and that of ice is 2.09 J/g °C.
57.5 kJ
What mass (in g) of O2 will be needed to burn 36.1g of B2H6?
B2H6 + 3O2 -> 2HBO2 + 2H2O
125 g
A sample of argon gas at STP occupies 56.2 L. Determine the number of moles of argon and the mass of argon in the sample.
2.509 moles
100. grams
What is the chemical formula of the precipitate that is formed when aqueous solutions of CdSO₄ and Li₂S are mixed?
CdS (s)