Exam (elaborations)
DAT GENERAL CHEMISTRY QUESTIONS AND ANSWERS WITH SOLUTIONS 2024
- Course
- Institution
DAT GENERAL CHEMISTRY QUESTIONS AND ANSWERS WITH SOLUTIONS 2024
[Show more]
Content preview
DAT GENERAL CHEMISTRYQUESTIONS AND ANSWERS WITH
SOLUTIONS 2024
Atomic Number - ANSWER number of protons found in that atom; low number; (Z)
Mass Number - ANSWER Protons + Neutrons; high number; (A)
Atomic Mass - ANSWER relative mass of that atom compared to the mass of a carbon-12 atom (which is
set at 12.00); measured in amu;
1 amu = - ANSWER 1.66x10^-24
Atomic Weight - ANSWER weight (g) of one mole (mol) of a given element (g/mol); the weighted average
of all the masses (not the weights) of an element, weighted according to the natural abundance of the
isotopic species of an element
1mol = ______ (Avagadro's Number) - ANSWER 6.022x10^23 molecules
Isotope - ANSWER multiple species of an atom with same number of protons and a different number of
neutrons (different mass numbers); generally exhibit same chemical properties
Ernest Rutherford - ANSWER 1911; gave experimental evidence that an atom has a dense, positively
charged nucleus that accounts for a small portion of the volume of the atom
Max Planck - ANSWER developed first quantum theory; 1900; proposed that energy emitted as
electromagnetic radiation from matter comes in discrete bundles called quanta; E=hv (h-Planck's
constant)
Planck's constant - ANSWER 6.626x10^-34 J*s
,The Bohr Model of the Atom - ANSWER developed 1913 model of H atom using Rutherford and Planck's
findings; H atom has central proton, electron travels around it in a circular orbit; centripetal force acting
on the electron as it revolved around the nucleus was the electrical force between the positively charged
proton and negatively charged electron; quantized angular momentum so it changed in discrete
amounts in relation to the quantum number (L=nh/2pi) n=quantum number h=Planck's constant; from
this Energy of an electron: E=-Rh/n^2, Rh=Rydberg constant 2.18*10^-18 J/electron
Rydberg Constant - ANSWER 2.18 x 10^-18 J/electron
Smaller orbit of electron the... - ANSWER lower the energy state
What is the Bohr Model used for? - ANSWER used to explain the atomic emission spectrum and atomic
absorption spectrum of hydrogen; because these spectrum are not the continuous spectrum that
classical physics would expect, they are line spectrum
Balmer Series - ANSWER 4 spectral lines that appear in the visible light region when a hydrogen atom
undergoes a transition from energy levels n>2 to n=2.
Lyman Series - ANSWER Set of spectral lines appearing in the UV region when a hydrogen atom
undergoes a transition from energy levels n>1 to n=1.
Heisenberg Uncertainty Principle - ANSWER impossible to determine the momentum and position of an
electron simultaneously; means if the momentum of an electron is being measured accurately, its
position will change and vice-versa
Pauli exclusion principle - ANSWER no 2 electrons in any given atom can possess the same set of four
quantum numbers (n, l, ml, ms)
Energy state of an electron - ANSWER the position and energy of an electron described by its 4 quantum
numbers (n, l, ml, ms)
quantum number n - ANSWER "principal quantum number"; gives info about the size of the orbital;
bigger n is, the bigger the radius of the orbital, the bigger the energy of the orbital; Max number of
electrons in an energy level = 2n^2
, quantum number l - ANSWER "Azimuthal (angular momentum) quantum number"; gives info about the
shape of the orbital; value of l = 0 to n-1 ; l=0=s; l =1=p; l=2=d; l=3=f; Max number of electrons that can
exist in a subshell= 4l +2; greater the value of l, the higher the energy of the subshell, but subshell
energies from different principal energy levels may overlap
quantum number ml - ANSWER "Magnetic Quantum number"; gives info about the orientation of an
orbital; value of ml = l to -l (includes 0);
quantum number ms - ANSWER "Spin Quantum number"; there are two spin orientations: +1/2 and -
1/2; whenever electrons are in the same orbital they must have opposite spins
List the Order the Energy Levels Fill - ANSWER Rule: n+l, and if that is the same number, then the one
with the lower n will fill first; 1s, 2s, 2p, 3s,3p,4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f...etc
Hund's rule - ANSWER dictates which orbitals within a subshell fill first; within a given subshell, orbitals
are filled so that there is a maximum number of half-filled orbitals with parallel spins
Paramagnetic - ANSWER material has unpaired electrons, magnetic field aligns the spins of these
electrons and weakly attracts the atom
Diamagnetic - ANSWER materials have no unpaired electrons and are slightly repelled by a magnetic field
Which are the valence electrons for groups IA and IIA? - ANSWER the outermost s electrons
Which are the valence electrons for groups IIIA through VIIIA (remaining column on right, excluding
weird middle metals)? - ANSWER the outermost s and p electrons
Which are the valence electrons for the transition elements? - ANSWER the outermost s electrons and
the second to outermost d shell
Dmitri Mendeleev - ANSWER published first version of periodic table; showed elements ordered by
atomic weight, produced patter of similar properties
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller Performance. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $14.49. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
77254 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now