Atomic Architecture Assessment
NGSS MS-PS1-1
Atomic Architecture Assessment
Modeling Simple Molecules & Extended Structures • Standard Assessment
Time Limit: 35 Minutes
Total Items: 10 Questions
Passing: 70% (7/10)
Student Name:
Date:
Class Period:
Score: _____ / 10
Model Color Key:
Carbon (C)
Hydrogen (H)
Oxygen (O)
Nitrogen (N)
Chlorine (Cl)
Sodium (Na)
1 Which of the following statements most accurately describes the fundamental difference between an atom and a molecule?
DOK 1
A An atom is made of two or more bonded elements, while a molecule contains only protons and electrons.
B An atom is the smallest basic unit of an element, whereas a molecule consists of two or more atoms bonded together.
C Molecules can only be formed when millions of identical atoms arrange in a repeating crystal lattice.
D Atoms only exist in solid materials, while molecules exist only in liquids and gases.
2 A student constructs the ball-and-stick model shown below to represent an organic fuel molecule. Based on the model, what is the chemical formula and total atom count for one molecule of this substance?
DOK 2
C O H H H H
Model Notes: Each sphere represents an individual atom, and connecting sticks indicate chemical bonds holding the discrete molecule together.
A \(CH_4O\) (or \(CH_3OH\)), containing 6 total atoms
B \(C_4HO\), containing 6 total atoms
C \(CHO\), containing 3 total atoms
D \(CH_3O_2\), containing 5 total atoms
3 Examine the two models below representing carbon monoxide (\(CO\)) and carbon dioxide (\(CO_2\)). Both molecules contain carbon and oxygen atoms.
DOK 2
Molecule X: C O
Molecule Y: O C O
Why do these two substances exhibit completely different physical and chemical properties even though they are made of the exact same elements?
A The carbon atom in Molecule X has more protons and electrons than the carbon atom in Molecule Y.
B The ratio and geometric arrangement of bonded atoms determine the unique identity and properties of each molecule.
C Molecule X is an extended crystalline solid at room temperature, while Molecule Y is a synthetic polymer.
D Oxygen atoms lose their mass when more than one bonds to a central carbon atom.
MS-PS1-1 Multiple Choice Assessment Page 1 of 3
Atomic Architecture Assessment | Part 1: Questions 4 - 6
Student: ______________________
4 Which characteristic correctly distinguishes an extended structure (such as diamond or table salt) from a simple molecule (such as water or methane)?
DOK 1
A Simple molecules form infinite 3D crystalline arrays, while extended structures only contain 2 to 5 atoms.
B Extended structures consist of repeating subunits bonded continuously throughout the material without a set molecular size.
C Extended structures contain only one type of subatomic particle, while simple molecules contain all three.
D Simple molecules can never exist as liquids or gases at standard room temperatures.
5 A science class analyzes microscopic structural models of two common solid minerals: Substance A and Substance B.
DOK 2
Substance A: Solid Carbon Dioxide
Individual 3-atom units separated by space
Substance B: Halite (Salt Crystal)
Continuous alternating 1:1 atomic network
Which classification and reasoning correctly interprets the structural models?
A Substance A is an extended structure because it contains multiple atoms; Substance B is a simple molecule because it forms a single crystal.
B Substance A is composed of simple discrete molecules; Substance B is an extended structure because atoms bond in an interconnected, repeating lattice.
C Both substances are simple molecules because both contain fewer than 20 total visible spheres.
D Neither substance has an atomic composition because they are solid minerals rather than chemical elements.
6 Synthetic plastics, such as polyethylene, are extended structures called polymers. The model below displays a segment of a polyethylene chain.
DOK 2
Repeating Subunit
Polyethylene polymer chain model segment (dashed blue box highlights one repeating unit)
Based on the model, what is the chemical composition of the basic repeating subunit (monomer) that forms this extended polymer?
A 1 Carbon atom and 1 Hydrogen atom (\(CH\))
B 2 Carbon atoms and 4 Hydrogen atoms (\(C_2H_4\))
C 6 Carbon atoms and 12 Oxygen atoms (\(C_6O_{12}\))
D 4 Carbon atoms and 2 Hydrogen atoms (\(C_4H_2\))
MS-PS1-1 Multiple Choice Assessment Page 2 of 3
Atomic Architecture Assessment | Part 2: Questions 7 - 10
Student: ______________________
7 Quartz (silicon dioxide, \(SiO_2\)) forms solid crystals. A microscopic sample contains approximately 20,000 silicon atoms bonded in a continuous 3D network. Based on MS-PS1-1 structural principles, how many oxygen atoms are bonded in this quartz crystal sample?
DOK 2
A Exactly 2 oxygen atoms, because \(SiO_2\) means only two oxygens can ever exist in a quartz sample.
B Approximately 40,000 oxygen atoms, because the extended structure maintains a consistent 1:2 repeating atomic ratio.
C Approximately 10,000 oxygen atoms, because extended structures always have twice as many silicon atoms as oxygen atoms.
D Zero oxygen atoms, because crystals only contain metal atoms in their repeating lattice.
8 A teacher asks four student lab groups to draw a particle model representing three separate molecules of ammonia (\(3 NH_3\)). Which group created the scientifically accurate model?
DOK 2
A
Group 1: One large bonded cluster containing 3 nitrogen and 9 hydrogen atoms (\(N_3H_9\)) connected together.
B
Group 2: Three separate, unbonded groups; each individual group has 1 nitrogen atom bonded to 3 hydrogen atoms.
C
Group 3: One cluster of 3 nitrogen atoms and three separate lone hydrogen atoms floating nearby.
D
Group 4: An infinite cubic grid with alternating nitrogen and hydrogen atoms in every direction.
9 Ethanol and dimethyl ether share the chemical formula \(C_2H_6O\), but ethanol is a liquid at room temperature (\(\text{bp } 78^\circ\text{C}\)) while dimethyl ether is a gas (\(\text{bp } -24^\circ\text{C}\)). Structural models show:
DOK 2
Ethanol: \(H_3C - CH_2 - O - H\)
|
Dimethyl Ether: \(H_3C - O - CH_3\)
What fundamental principle about molecular models does this evidence demonstrate?
A Molecules with the same atom counts can have different properties when atomic connectivity and arrangement differ.
B Chemical formulas are inaccurate models that cannot represent real physical matter.
C Liquids always contain more total mass than gases even when chemical formulas are identical.
D Oxygen atoms can only bond when connected to two carbon atoms at the same time.
10 Students investigated four unknown substances (W, X, Y, Z) and recorded their microscopic model observations:
DOK 2
| Substance | Microscopic Model Observation | Independent Unit |
|---|
| Substance W | Crystalline lattice with infinite repeating Na and Cl pattern | Continuous 3D network |
| Substance X | Separate clusters each with 12 C, 22 H, and 11 O atoms | Individual \(C_{12}H_{22}O_{11}\) molecule |
| Substance Y | Rigid repeating interlocking grid of pure Carbon atoms | Continuous 3D network |
| Substance Z | Separate diatomic pairs of Iodine atoms (\(I_2\)) | Individual \(I_2\) molecule |
Which pair of substances should be classified as extended structures?
A Substance W and Substance Y
B Substance X and Substance Z
C Substance W and Substance X
D Substance Y and Substance Z
MS-PS1-1 Multiple Choice Assessment Page 3 of 3
