Chem 161 - Study guides, Class notes & Summaries

Chem 161 Lecture 4 2023 UPDATE RATED A+ What is the threshold frequency? v0 = if you vary the frequency of the incident light, it is found that there is a certain minimum threshold frequency below which no electrons are emitted What happens if you are below the threshold frequency? No electrons are emitted regardless of the brightness of the light What happens if you are above the threshold frequency? Electrons are emitted, and the higher the frequency, the higher the KE of the emitte...

Chem 161 Lecture 7 Answers 2023 UPDATE RATED A+ What is ionic lattice? An ionic lattice is a long-range array of positive and negative ions, held together by electrostatic attraction What is ionic lattice measured in? kJ/mol What does lattice energy depend on? These comparisons can be answered by recognizing that lattice energy depends on both the charge of the ion and the size of each ion—which determines the distance between the oppositely charged ions What formula shows the for...

scientific theory explains how/why. based on observations/experiments, makes testable predictions, changes over time based on new evidence, can be falsifiable scientific law predicts what happens

Chem 161 Lecture 3 Answers 2023 UPDATE RATED A+ What is a mole? number of atoms that has a mass equal to the AMU in grams What is Avogadro’s number? 6.022 x 10^23 atoms/mole What is wavelength? distance between each wave unit λ What is frequency? # of waves (cycles) per second What are units of wavelength? m, mm, nm (length of each λ) What are units of v? cycles/sec waves/sec sec^-1 Hz (heartz) What is the velocity of the wave? λ * v = velocity of wave (meter/wave) * (wave/s...

Chem 161 Lecture 5 Answers LATEST UPDATE 2023 RATED A+ What are the four quantum values? n is the principal quantum number. It determines the main energy level. Values of n are 1,2,3,4,5,…… ℓ is the angular momentum quantum number. It determines the shape of the orbital Values of ℓ vary from 0 to n-1 mℓ is the magnetic quantum number. It determines the orientation of the orbital. Values of mℓ vary from -ℓ to +ℓ What is n? principal quantum number What does n determine...

CHEM 161 EXAM 2 2024/25; Questions and Answers 100% Solved actual yield the experimental quantity, in grams, of product obtained in a reaction. Avogadro’s number the number of particles (6.022 x 10^23) of a substance in 1 mol of that substance. By definition, Avogadro’s number is equal to the number of carbon-12 atoms in exactly 12.00 g of carbon-12. balanced

Beta particle emission that is a high energy electron. the electron comes from a neutron so when it is emitted, the atomic number goes up by one, but the atomic mass remains the same alpha particle emission that is basically a helium nucleus (2+ charge), so when it is emitted the atomic number goes down by 2 and the atomic mass goes down by 4

How can matter be classified? Matter: Purity: 1. Pure Substances A. Elements B. Compounds 2. Mixtures A. Homogenous Solutions B. Heterogenous Solutions