Exam 1
How many significant figures are in 0.01034
4.000 sig figs
What is the oxidation number of lead in PbO2
+4
When filled, how many electrons can the f subshell hold?
14
An element is what row (and below) can have an expanded octet?
Row 3
What is the most abundant element in the universe?
Hydrogen
An atom of strontium-90 contains...
38 electrons, 38 protons, 52 neutrons
What is the theoretical yield of water if 26.0 g of O2 are reacted?
29.25 g of H2O
If 1 mol of gas at STP is 22.4 L what will happen to the volume if the temperature is changed to 20 C
The volume will increase
What is the steric number of ICl3
5
What is Avogadro's number?
6.023 x 1023
The element X occurs naturally to the extent of 20.0% X12 and 80.0% X13. The atomic mass of X is near
12.8 amu
If 500.0 mL of 1 M HCl is diluted to 1.5 L what is the final molar concentration?
0.33 M
If 2L of H2 gas is formed how much Na was reacted?
2Na+2H2O --> 2NaOH+H2
4.1 g
Which of the following is planar?
a. NH3
b. SO32-
c. CO32-
d. CCl4
C
Dry ice is the solid form of what compound?
CO2
Determine the number of moles of oxygen (O) in 235 mg of Al2(CO3)3
0.00904 mol of O
Calculate the mass of SbF3 required to produce 1.00 g of CCl2F2 via the following chemical equation. (MM SbF3: 179 g/mol, CCl2F2: 121 g/mol)
3CCl2F2 + 2SbF3 → 3CCl2F2 + 2SbCl3
0.986 g
What is the wavelength of a photon emitted when an electron fall from level 4 to 2 in a hydrogen atom?
486 nm
For which molecule can the bonding be described in terms of sp3 hybrid orbitals on the central atom? a.SF6 b. BF3 c. PCl5 d. NH3
D
What color is liquid oxygen
Blue
If percent composition is C-68.3%, H-6.3%, N-3.8%, O-21.6% what is the empirical formula?
C21H23NO5
If 30.0 mL of NaOH is required to titrate 50.0 mL of 0.25 M HCl what is the molarity of NaOH?
0.42 M
What is the electron configuration of Ca2+
1s2 2s2 2p6 3s2 3p6
Is HSO3- a polar molecule?
Yes
What are the two metals that lack a silvery appearance
Gold and copper