Unit 1: Atomic Theory
Who discovered the nucleus?
Ernest Rutherford
Scandium has __ protons, __ neutrons, and __ electrons
21 protons, 24 neutrons, and 21 electrons
The elements of group 2A will all form ions. These ions will be ______ and will have ____ charge.
cations, 2+
List the type of each reaction below: (S, D, DR, SR, C)
1. 4Na + O2 --> 2Na2O
2. Cl2 + 2KBr --> Br2 + 2KCl
3. NH4NO2 --> N2 + 2H2O
4. Sb2S3 + 6HCl --> 2SbCl3 + 3H2S
5. 2C3H6O2 + 7O2 --> 6CO2 + 6H2O
1. S
2. SR
3. D
4. DR
5. C
A solution turns blue litmus paper red. Is it an acidic or basic solution?
Acidic
What did J.J. Thomson discover in the cathode ray experiment?
As you move top to bottom in Group 2 from beryllium through radium, atomic size
increases
To what group of the periodic table does element X belong if it forms the ion X-2 ?
Group 6A
Which type of chemical reaction will the following be classified as: redox, precipitation, or acid-base?
H2S(g) + Cl2(g) --> S(s) + 2HCl(g)
redox reaction
What is the [H+] of solution with a 3.12 pH?
7.56 x 10-4 M
The first scientist to develop a model of the atom which he described as looking like “plum pudding”
J.J. Thomson
Rank the following elements in increasing electronegativity: As, Cr, Br, K
K, Cr, As, Br
What is the correct name of SF5?
sulfur pentafluoride
In the following redox reaction, the oxidation state of iron goes from ___ to ___.
Fe2O3 + 3CO --> 2Fe + 2CO2
+3 to 0
A solution with a pH of 4.0 ____.
a. is basic
b. has a hydrogen-ion concentration of 4.0 M
c. is neutral
d. has a hydroxide ion concentration of 1 x 10-10 M
d.
In Rutherford's Gold Foil Experiment, most of the alpha particles ____________ ________ the gold foil, showing that the nucleus is very ______.
In Rutherford's Gold Foil Experiment, most of the alpha particles passed through the gold foil, showing that the nucleus is very small.
What periodic family is highly reactive, are nonmetals, and can be solids, liquids, or gases at room temperature?
Halogens
What is the correct formula for nickel(III) carbonate?
Ni2(CO3)3
List the coefficients of the balanced chemical equation AND state the specific type of reaction (redox, acid-base, or precipitation)
H3PO4 + KOH --> K3PO4 + H2O
1, 3, 1, 3
Acid-Base Reaction (Neutralization Reaction)
What is the pH of a 2.1x10-5 KOH solution?
9.32
This model of the atom describes the probability of finding electrons within given orbitals, or three-dimensional regions of space, within an atom.
The Quantum Mechanical Model
How many valence electrons are in the following atom:
1s22s22p63s23p64s23d8
2 valence electrons
Identify the polar molecules in the following group:CCl4, CO2, HCl
HCl
When copper is placed in silver nitrate solution, a chemical reaction occurs. Solid silver metal precipitates out of the solution and aqueous copper(III) nitrate forms. Write the balanced chemical equation for this reaction.
Cu(s) + 3AgNO3(aq) --> 3Ag(s) + Cu(NO3)3(aq)
What are the correct products for the following acid-base reaction?
H2SO4 + 2KOH
K2SO4 + 2H2O