Grade 9 Exam: Scientific Method, Matter, Atoms

Abigail is curious about why the leaves change color in the fall. What is the first step of the scientific method she should use to find out?

• Mix different colored paints together

• Make an observation or ask a question

• Look up the information online

• Guess the answer

Maya, Mia, and Evelyn are discussing scientific concepts. Maya says a hypothesis is a proposed explanation for a phenomenon, while a theory is a well-substantiated explanation based on evidence and experimentation. Mia and Evelyn are unsure. Can you tell them the difference between a hypothesis and a theory?

• A hypothesis is used in physics, while a theory is used in chemistry

• A hypothesis is always correct, while a theory can be proven wrong

• Maya is correct. A hypothesis is a proposed explanation for a phenomenon, while a theory is a well-substantiated explanation based on evidence and experimentation.

• A hypothesis is based on evidence, while a theory is just a guess

Tags

NGSS.MS-LS1-5

NGSS.MS-PS2-4

Mia, Nora, and Jackson are conducting a science project. Why is it important for them to conduct experiments as part of their project?

• To make a guess and hope for the best.

• To follow the crowd and do what everyone else is doing.

• To waste time and resources.

• To test hypotheses and gather empirical evidence.

Tags

NGSS.MS-ETS1-3

NGSS.MS-LS2-4

Evelyn, Hannah, and Priya are learning about different states of matter in their science class. They learned that there are three common states. Can you recall what they are?

• solid, liquid, and gas

• solid, gas, and air

• solid, liquid, and plasma

• liquid, gas, and energy

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

Harper, Abigail, and David were discussing the properties of matter during their science project. They were particularly interested in the difference between a solid and a liquid. Can you help them understand this difference?

• Solids, like the desk they were using, are always hot, while liquids, like the water they were drinking, are always cold

• Solids, like the blocks they were using for their project, have a fixed shape, while liquids, like the paint they were using, take the shape of their container

• Solids, like the glass window in their classroom, are transparent, while liquids, like the milk they had for lunch, are opaque

• The molecules in a solid, like the wooden blocks they were using, are tightly packed and vibrate in place, while the molecules in a liquid, like the water they were drinking, are more loosely packed and can move around each other.

Tags

NGSS.5-PS1-3

Nora, Evelyn, and Aiden are conducting an experiment in their science class. They are observing a balloon filled with gas that is being heated. What happens to the particles in the gas inside the balloon when it is heated?

• The particles lose kinetic energy and move slower, causing the gas to expand

• The particles gain kinetic energy and move faster, causing the gas to expand.

• The particles gain kinetic energy and move slower, causing the gas to contract

• The particles gain potential energy and move slower, causing the gas to contract

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

NGSS.MS-PS3-5

Isla, Zoe, and Michael are studying the structure of an atom for their science project. They are discussing the three main subatomic particles that make up an atom. What are these particles?

• neutrons, positrons, electrons

• protons, neutrons, and electrons

• protons, electrons, photons

• quarks, leptons, bosons

Tags

NGSS.MS-PS1-1

Maya, Aiden, and Lily are studying chemistry and they come across an element. They are curious to know how the atomic number of this element is determined. What should they do?

• Count the number of electrons in the nucleus of its atom.

• Determine the color of the element.

• Count the number of protons in the nucleus of its atom.

• Measure the mass of the atom.

Liam, Evelyn, and Grace are studying atomic models in their physics class. Their teacher asks, 'What is the Bohr model of the atom that we discussed in class?'

• A model that Liam suggested, which depicts the atom as a linear chain of protons and neutrons

• A model that Evelyn thought of, which depicts the atom as a cloud of positive and negative charges

• A model that Grace believed in, which depicts the atom as a solid, indivisible sphere

• A model that their teacher explained, which depicts the atom as a small, positively charged nucleus surrounded by electrons that travel in circular orbits around the nucleus.

Benjamin, Kai, and Priya are discussing atomic theories in their science class. They are trying to understand the difference between Dalton's atomic theory and modern atomic theory. Can you help them?

• Benjamin suggests that in Dalton's atomic theory, atoms are constantly changing, while modern atomic theory states that atoms are stable and unchanging.

• Kai thinks that in Dalton's atomic theory, atoms are indivisible and indestructible, while modern atomic theory includes subatomic particles and the ability to split atoms.

• Priya believes that Dalton's atomic theory includes the concept of isotopes, while modern atomic theory does not.

• They also consider the idea that in Dalton's atomic theory, atoms are made of protons, neutrons, and electrons, while modern atomic theory states that atoms are made of only protons and electrons.