Chemistry Quiz

A class uses 10 students to model a lithium atom. Each student represents a particle in the atom. Three students wear signs with a “+” sign, representing (electrons / neutrons / protons / isotopes). The four students with “0” signs represent (neutrons / protons / electrons / isotopes). Each of the remaining students wears a "-" sign, representing (protons / electrons / isotopes / neutrons). Write the letters of the correct answers on the lines at left.

• electrons

• neutrons

• protons

• isotopes

Tags

NGSS.MS-PS1-1

George is writing an essay about the role of observation and inference in the development of the atomic theory. He wants to explain why it was more difficult to observe the presence of neutrons in atoms. Which statements should he include in his essay? Choose the two statements that apply.

• While protons or electrons can be influenced by other charged particles, neutrons are not.

• It was difficult to observe that neutrons were different than protons because the two particles respond to charge in the same way.

• It was difficult to observe that neutrons were different than electrons because the two particles respond to charge in the same way.

• Neutrons are held tightly together with protons in the nucleus, so scientists could not observe the behavior of neutrons independently.

Tags

NGSS.HS-PS1-8

Many events are periodic. The seasons and the calendar are periodic. If you have a music lesson every Tuesday after school, it is a periodic event. Which statement best explains why the table of elements is periodic?

• All elements are included in the table.

• It has rows and columns, as a calendar does.

• Properties of the elements repeat in a cycle or repeating pattern.

• It has many different parts, each of which is different from other parts.

An electrical engineer is choosing an element to use for a wire with high conductivity. She should choose an element that is a(n) (alkaline earth metal / transition metal / group 1 metal / alkali metal). She should not choose a metal from one of the other categories because they are too (unreactive / malleable / ductile / reactive). Write the letters of the correct answers on the lines at left.

• alkaline earth metal

• transition metal

• group 1 metal

• alkali metal

Tags

NGSS.MS-ETS1-1

In 1986, there was an accident that led to an explosion at the Chernobyl Power Plant in what was then the Soviet Union. Soon after, people started to notice something horrifying. A radioactive element released during the explosion was replacing calcium in people's teeth and bones! The element had chemical properties similar to calcium. Which elements are likely to have similar properties to calcium because they have the same number of valence electrons as calcium?

• carbon (C), phosphorus (P)

• cobalt (Co), nickel (Ni)

• gallium (Ga), indium (In)

• magnesium (Mg), strontium (Sr)

Tags

NGSS.HS-PS1-1

Many gems are silicates, which are compounds that contain both silicon (Si) and oxygen (O). Which statements correctly compare silicon and oxygen? Choose the two statements that apply.

• Silicon is a metalloid and oxygen is a nonmetal.

• Silicon has a lower boiling point than oxygen.

• Silicon has a higher boiling point than oxygen.

• Silicon and oxygen each have six valence electrons.

Tags

NGSS.HS-PS1-1

Heidi is using the periodic table to make predictions about chemical reactions. She knows that sodium is a reactive metal. Which element is most likely to form a molecule with sodium that includes one ionic bond?

• Potassium (K)

• Oxygen (O)

• Fluorine (F)

• Aluminum (Al)

Water (H₂O) and hydrogen fluoride (HF) are both polar molecules. Which of the following statements are true about the attractions between water and hydrogen fluoride when they are mixed together? Choose the two statements that apply. (Hint: In HF, the F atom attracts the shared electron more than the H atom.)

• The H in HF and the H in H₂O attract each other.

• The H in HF and the O in H₂O attract each other.

• The F in HF and the H in H₂O attract each other.

• The F in HF and the O in H₂O attract each other.

Tags

NGSS.HS-PS1-3

Nick is researching why baking powder is a common baking ingredient. He learns that baking powder contains tartaric acid and sodium hydrogen carbonate. He also learns that when water is added to cake ingredients, a reaction occurs. It causes bubbles to form that make the cake rise. What gas is in the bubbles, and why do they form?

• Carbon dioxide gas forms because an acid and a carbonate react.

• Carbon dioxide gas forms because an acid and a base react.

• Hydrogen gas forms because an acid and a metal react.

• Hydrogen gas forms because an acid and a base react.

Tags

NGSS.MS-PS1-2

The atomic structure of an element that is a key ingredient in soft drinks is modeled below. It is in a compound that makes a soft drink tart. Look at the diagram and the periodic table. Which element is represented by the diagram?

• arsenic (As)

• nitrogen (N)

• phosphorus (P)

• sulfur (S)

Tags

NGSS.MS-PS1-1