The Beginning
Which subatomic particle determines the charge of an atom or compound?
The electron
There are two isotopes of a compound, one which weighs 54g and one which weighs 55g. The 54g isotope is 37.5% abundant in nature. What is the molecular weight of the compound?
54.625 g
Which element has a greater difference in energy between first and second ionization energy: K or Mg?
What are the bond angles for a trigonal planar molecule?
120°
What happens to the volume of a gas when the pressure is doubled by STP?
The volume decreases by a factor of 2
If an element from group 1 were to bond with an element from group 7, what kind of bond is occurring?
An Ionic Bond
In the formation of methanol (CH3OH), hydrogen combines with carbon monoxide. If 24.67 g of hydrogen and 17.3 g of carbon dioxide are used in this reaction, how many grams of methanol can be formed?
19.79 g methanol
What is the formula to find the bond energy of a reaction?
Sum bonds broken - sum of bonds formed
The central atom of a compound has 5 bonding/electron groups surrounding it. What is the hybridization of the central atom?
dsp³
You are studying three covalent compounds with three very different boiling points. All of the compounds have similar molar mass and relative shape. Explain how these compounds can have very different boiling points.
Each compound contains a different intermolecular force.
How many molecules are contained within 4.58 g of SO₃?
3.445E22 molecules
Calculate the frequency of a photon absorbed when a hydrogen atom experiences a transition from n=2 to n=4.
6.17E14 Hz
Which of the following is not a possible mₗ value for n=2: -1, 1, 2?
2
Will the following reaction form a precipitate? What are the products of the reaction? CaCl₂ + Na₂SO₄
Yes, CaSO₄ will precipitate out. The full reaction is: CaCl₂ + Na₂SO₄ → 2NaCl + CaSO₄
What volume of 0.0200 M calcium hydroxide in mL is required to neutralize 35 mL of 0.0500 M nitric acid?
43.75 mL
What is the formula for potassium permanganate?
KMnO₄
What is the empirical formula for a compound containing 31.5% Al, 56.1% O, and 12.4% S by mass?
Al₃O₉S
Name the following compound: HCO₃⁻.
Bicarbonate or hydrogen carbonate
Draw the lewis structure for XeF4 on the board. What is the molecular geometry and electron geometry?
Square planar and octahedral
At a given temperature and pressure, a sample of gas A is observed to diffuse twice as fast as an equal-sized sample of a different gas B. What is the ratio of the molar mass of gas A to gas B?
1:4
The blue color of fireworks is often achieved by heating copper (I) chloride to 1200℃. Then, the compound emits a blue light which has a wavelength of 450 nm. What is the quanta of energy emitted by this process?
4.41E-19 J
Determine the bond order for C₂⁻. Is it paramagnetic or diamagnetic?
5/2, paramagnetic
Order the following ions from smallest to largest atomic radius: Ca²⁺, Br⁻, Al³⁺, K⁺, and O²⁻
Al³⁺ < Ca²⁺ < K⁺ < O²⁻ < Br⁻
Balance the following redox reaction: PbO + NH₃ → N₂ + Pb.
3PbO + 2NH₃ → N₂ + 3Pb + 3H₂O
After balancing the following redox reaction in acidic/aqueous solution, what is the sum of all coefficients? Cu²⁺ + Ce³⁺ → CeO₂ + Cu
Cu²⁺ + 2Ce³⁺ + 4H₂O → 2CeO₂ + Cu + 8H⁺
Sum: 18