Unit 0
What are the two classes of matter and which one includes diatoms?
pure substances(includes diatoms) & mixtures
An element has the following natural abundances and isotopic masses: 90.92% abundance with 19.99 amu, 0.26% abundance with 20.99 amu, and 8.82% abundance with 21.99 amu. Calculate the average atomic mass of this element.
20.16 amu
Name this compound: Fe2O3
Iron (III) Oxide
How many atoms are in 2.73 moles of sodium phosphate?
1.32 x 1025 atoms Na3PO4
Name the five periodic trends we covered and how they increase on the periodic table. *Bonus points if you can tell me all the definitions*
Atomic Radius increases as you down and to the left.
Effective Nuclear Charge, Electron Affinity, Ionization Energy, and Electronegativity increase as you go up and to the right.
How many significant figures are appropriate to show in the final result of this problem:
((13.7034+0.02734) - (10.890+0.87)) x 7.1
2 sig figs
Find the number of protons, neutrons, and electrons if the atomic number is 23, and the atomic mass is 74.
protons-23, electrons-23, neutrons-51
Name this compound and draw its Lewis structure: BCl3
boron dichloride
(see screen for diagram)
How many atoms are in 15g of methane (CH4)?
2.82 x 1024 atoms CH4
Find the empirical formula of a compound with 88.8% Cu and 11.2% O.
Cu2O
0.02L
What is electronegativity?
the ability of an atom to attract electrons when the atom is in a compound
Between the two compounds, which one would have a higher melting point: NaCl or CH3OH?
NaCl because it is ionic
What is the volume of 12.0g of CL2 gas @ STP?
7.58L Cl2 @ STP
Tell me the shape, type of force, and if this molecule is polar or nonpolar: Cl2O
bent, polar, dipole-dipole forces
Complete this problem with the correct number of sig figs and units: (4.05x1025m)(2.6x1023m)
1.1 x 1048 m2
Is Yttrium a transition metal? Why or why not?
Y is a transition metal because it has an incompletely filled d subshell.
What is the molecular shape for this compound, and is it polar or nonpolar: SeO3
Trigonal Planar; nonpolar
What is the percent composition of a compound that contains 40.8g C and 54.4g O?
42.86% C, 57.14% O
Write the electron configuration and core notation for Sn2+
The average adult has 5.2 L of blood in their body at any given time. What is the volume of blood in cubic meters?
5.2 x 10-3m3
Determine the allowed set of quantum numbers for 3d.
n=3
l=0; ml=0; Ms= +/- 1/2
l=1; ml=-1,0,+1; Ms= +/- 1/2
l=2; ml=-2,-1,0,+1,+2; Ms= +/- 1/2
Which of the three intermolecular forces has the strongest bond? Give an example of a compound that has that type of force.
hydrogen bonding; H2O
Calculate the molecular formula for the compound: 94.1% O and 5.9% H (MW = 34 g/mol)
H2O2
CO2 is nonpolar, while HCN is polar. Tell me why one is polar and the other is nonpolar if they both have a linear geometry.
CO2 has two oxygen's on both sides, so the dipoles are balanced out and cancel each other. HCN has two different elements on either side and the dipoles are unbalanced, therefore there is a net dipole making this molecule polar.