Bohr theory - Study guides, Class notes & Summaries

Chem 219: Exam 2 Questions With 100% Correct Answers The atomic radii of zirconium (Zr) and hafnium (Hf) are nearly the same despite the fact that hafnium has 32 more protons and electrons. Which of the following bests explains this phenomenon? - answerHafnium contains electrons in the 4f orbitals. These 4f electrons do not effectively shield the higher nuclear charge and thus Zeff is higher than might be otherwise expected. Which of the following is true concerning successive ionizations...

ACS GEN CHEM 1 FINAL Exam 166 Questions with Verified Answers The physical material of the universe. It is anything that has mass and occupies space. - CORRECT ANSWER Matter is made up of relatively few elements. - CORRECT ANSWER Matter The smallest building block of matter. Smallest particle that retains the chemical property of the element (O, He, S). - CORRECT ANSWER Atom Each _______ is made of the same kind of atom - CORRECT ANSWER Element Combination of atoms held together i...

Chapter 01 - Molecular Reasons 1. Which of these is the best definition of matter? a. b. c. d. e. ANSWER: POINTS: The pull of gravity on an object. Anything that has weight and volume. Anything that has mass and occupies space. Anything that is directly proportional to weight. The measure of the amount of space an object occupies. 2. Which of these statements is correct? a. Theamountofcarbononearthisessentiallyconstant. b. The amount of carbon on earth fluctuates with the seasons. c....

ACS Gen Chem 1 Exam 89 Questions with Verified Answers Extensive Property - CORRECT ANSWER Values that depend on how much you have Intensive property - CORRECT ANSWER Independent of size sample Density - CORRECT ANSWER Mass/volume Homogeneous mixture - CORRECT ANSWER Same throughout, indistinguishable parts Heterogeneous - CORRECT ANSWER Different parts, distinguishable parts Diatomic elements - CORRECT ANSWER N2, O2, H2, Cl2, Br2, I2 John dalton - CORRECT ANSWER Founded the...

What are the properties of group 1 metals? - Ans .Can be cut with a knife Shiny, but tarnish quickly with air, because a layer of oxide is formed Good conductors of electricity (Like all metals) Low density Low melting point What are the properties of group 7? - Ans .• All gain an electron during their reactions • They are poisonous • 7 electrons in their outer shells • when they gain an electron they form hallide ions What is the trend in reactivity of group 1? - Ans .The react...

Chapter 1—Molecular Reasons MULTIPLE CHOICE 1. Which of these is the best definition of matter? a. The pull of gravity on an object. b. Anything that has weight and volume. c. Anything that has mass and occupies space. d. Anything that is directly proportional to weight. e. The measure of the amount of space an object occupies. ANS: C PTS: 1 2. Which of these statements is correct? a. The amount of carbon on earth is essentially constant. b. The amount of carbon on earth fluctuates...

CHEM 121 FINAL EXAM | UPDATED QUESTIONS AND ANSWERS UPDATED .Buy Quality Materials! describe photoelectric effect light shining on certain materials cause it to emit electrons define a collapse in terms of quantum theory collapse of probability once something happens, there is no more probability for what it could be. it is what it is. describe the stationary state hypothesis as per Bohr, electrons dont emit radiation unless theres a reason for the energy level of the electron to ch...

FTCE Middle Grades Science 5-9 Exam 406 Questions with Verified Answers Which of the properties listed below is a characteristic of a liquid but not of a gas? A. It has the ability to flow. B. It maintains its volume in an open container. C. Its molecules are constantly in motion. D. Its volume varies depending on temperature. - CORRECT ANSWER B A 0.100 m3 chamber is filled with oxygen gas at standard conditions (101 kPa at 273 k). Assuming ideal conditions and behavior, what will be t...

ion - correct answer a molecule with a charge cation - correct answer a molecule with a positive charge anion - correct answer a molecule with a negative charge solid - correct answer definite shape and volume liquid - correct answer definite volume, takes the shape of its container gas - correct answer indefinite shape and volume plasma - correct answer matter stripped of its electrons that gives of light solution - correct answer made of a solute and solvent heterogeneo...

AC HPAT Chemistry Questions All Correct Answers single displacement - ANSWER- A + BC --> AC + B double displacement - ANSWER- AB + CD --> AD + CB precipitate - ANSWER- A solid that forms from a solution during a chemical reaction. energy level - ANSWER- Energy levels (also called electron shells) are fixed distances from the nucleus of an atom where electrons may be found. What is the atomic number of an element - ANSWER- number of protons What is the mass number of an element - A...