Light Energy
What is the relationship between wavelength and frequency in electromagnetic radiation?
They are inversely proportional: as wavelength increases, frequency decreases.
What is the electron configuration of oxygen in full notation?
1s22s22p4
Name the compound CO2
Carbon dioxide.
Name NaCl
Sodium chloride.
What is the formula and charge of the nitrate ion?
NO3−
What is the energy (in joules) of a photon with a frequency of 6.00×1014 Hz?
E=hν=(6.63×10−34)(6.00×1014)≈3.98×10−19J
Which sublevel fills after 4s?
3d
Name N2O5
Dinitrogen pentoxide.
Name Ca(NO3)2
Calcium nitrate.
What is the name of SO32−?
Sulfite.
Which region of the electromagnetic spectrum has the shortest wavelength but highest energy?
Gamma rays
How many valence electrons does sulfur have, and why?
6; it is in group 16 (6A), so it has six electrons in its outermost shell. / it has 6 electrons on the 3rd energy level.
What is the formula for sulfur hexafluoride?
SF6
What is the formula for aluminum oxide?
Al2O3
Which polyatomic ion has the formula NH4+?
Ammonium.
Why do hydrogen atoms produce only four visible spectral lines?
Because only four electron transitions in hydrogen fall within the visible range. / Line spectra phenomenon.
Write the noble gas shorthand configuration for molybdenum
[Kr] 5s¹ 4d⁵
Why do we use prefixes like “mono-” and “di-” in covalent compound names but not in ionic compounds?
Because covalent compounds can form multiple ratios of the same elements (with different properties), so prefixes clarify the exact number of atoms.
Explain why Roman numerals are used in names like iron(III) chloride.
Because transition metals can form multiple cations with different charges, so the numeral indicates the charge.
Write the formula for perchlorate.
ClO4−
Explain why blue light has higher energy than red light using the photon energy equation.
E=hc/λ; blue light has a shorter wavelength than red light, so its energy per photon is greater.
Predict the electron configuration of the sulfide ion S2- and explain how it relates to the octet rule.
Sulfur has 16 electrons in its neutral state (1s22s22p63s23p4). When it gains two electrons to form S2−, the configuration becomes (1s22s22p63s23p6), achieving a full octet like argon.
Name the compound P4O10
Tetraphosphorus decoxide
Name CuSO4
Copper (II) sulfate
A compound contains both carbonate and hydroxide ions and has the formula M(CO3)(OH), where M is a metal cation. If the metal is in Group 13, identify the metal and write the full name of the compound.
The metal is aluminum (Al3+), so the compound is aluminum carbonate hydroxide.