Download UNIT 3 VOCABULARY MATCHING and mole problems

UNIT 3 VOCABULARY MATCHING
WORD BANK
(A) electron
(E) mass number
(I) electron cloud
(B) neutron
(F) isotope
(J) Thomson
(C) proton
(G) nucleus
(K) Bohr
(D) atomic number
(H) Dalton
(L) Rutherford
____ 1.) center part of an atom; contains almost all of the mass of an atom
____ 2.) equal to the number of protons in an atom; whole number on the Periodic Table
____ 3.) equal to the number of protons plus the number of neutrons in an atom
____ 4.) discovered the electron using a cathode ray tube
____ 5.) atoms of the same element, but have different masses
____ 6.) negatively-charged subatomic particle
____ 7.) part of the atom that surrounds the center; accounts for almost all of the volume of an atom
____ 8.) discovered the nucleus with the gold foil experiment
____ 9.) positively-charged subatomic particle
____ 10.) established that atoms of one element are not changed into atoms of another element in a
chemical reaction
____ 11.) hypothesized that electrons travel around the center of the atom in particular paths
____ 12.) subatomic particle with no charge
WEIGHING & COUNTING ATOMS
Multiple Choice
1. The atomic number of oxygen, 8, indicates that there are eight
(A) protons in the nucleus of an oxygen atom
(B) oxygen nuclides
(C) neutrons outside the oxygen atom's nucleus
(D) energy levels moving around each oxygen nucleus
2. The number that is the total number of protons and neutrons in the nucleus of an atom is the
(A) atomic number
(B) Avogadro number
(C) mass number
(D) number of neutrons
3. Isotopes of a particular element differ in
(A) the number of neutrons in the nucleus
(B) atomic number
(C) the number of electrons in their outermost energy level
(D) the total number of electrons
4. In determining atomic mass units, the standard is a(n)
(A) C - 12 atom
(B) C - 14 atom
(C) H - 1 atom
(D) O - 16 atom
5. The chemical shorthand for atomic mass units is
(A) amu
(B) mu
(C) a
(D) am
6. The average atomic mass of an element is the weighted average of the atomic masses of the
(A) naturally-occurring isotopes
(B) two most abundant isotopes
(C) nonradioactive isotopes
(D) artificial isotopes
7. The number of atoms in one mole of carbon is
(A) 6.022 x 1022
(B) 6.022 x 1023
22
(C) 5.022 x 10
(D) 5.022 x 1023
8. The number of atoms in a mole of any substance is called
(A) the atomic number
(B) Avogadro's number
(C) the mass number
(D) the molar mass
9. As the atomic masses of the elements in the Periodic Table increase, the number of atoms in one
mole of each element
(A) decreases
(B) increases
(C) remains the same
(D) becomes a negative number
Problems
1. How many moles are equal to 2.548 grams of boron trifluoride, BF3?
2. How many grams are there in 2.45 x 1024 molecules of ammonia, NH3?
3. How many moles are equal to 5.29 x 1023 atoms of carbon?
4. What is the mass (in grams) of 6.759 moles of sodium chloride, NaCl?
5. How many molecules of H3PO4 are contained in 0.257 moles of H3PO4?
6. How many atoms of copper are equal to 49.5 grams of copper?
7. What is the mass (in grams) of 7.14 x 1023 molecules of C6H12O6?
8. How many moles are equal to 8.392 x 1023 atoms of uranium?
9. What is the mass (in grams) of 5.685 moles of sodium bicarbonate, NaHCO3?
10. How many molecules are equal to 0.027 moles of calcium carbonate, CaCO3?
11. How many moles are equal to 93.75 grams of sodium sulfate, Na2SO4?
12. How many molecules are equal to 103.74 grams of lead nitrate, Pb(NO3)2?