Unit 1 Retake Study Guide

The atoms in an element are __________ in different states of matter.

• invisible

• different

• identical

• variable

• visible

Answer explanation

The atoms in an element are identical regardless of the state of matter they are in. This means that all atoms of a given element have the same number of protons and similar properties, making 'identical' the correct choice.

Tags

NGSS.MS-PS1-4

Luna is conducting an experiment with a piece of wood and a metal ball. She observes that the wood will ______ if it is more dense and ______ if it is less dense than the water it is placed in.

• float, sink

• sink, float

• rise, fall

• fall, rise

Answer explanation

Luna's observation aligns with the principle of buoyancy: an object will sink if it is denser than the fluid (water) and float if it is less dense. Therefore, the correct completion is 'sink' if more dense and 'float' if less dense.

Aria and David are conducting an experiment with a density column. The ______ dense liquid will sink to the bottom and the ______ dense liquid will be at the top.

• more, less

• less, more

• equally, more

• more, equally

Answer explanation

In a density column, the more dense liquid sinks to the bottom due to its greater mass per unit volume, while the less dense liquid rises to the top. Therefore, the correct answer is 'more, less'.

As Mia heats a metal rod, the motion of the atoms ______.

• decreases

• stops

• increases

• remains the same

Answer explanation

As Mia heats the metal rod, the energy increases, causing the atoms to move more vigorously. Therefore, the correct answer is that the motion of the atoms increases.

Tags

NGSS.MS-PS1-4

Charlotte is observing different states of matter. She notices that atoms move the fastest as a

• Solid

• Liquid

• Gas

• Plasma

Answer explanation

Atoms move fastest in a gas because they have more energy and are less tightly packed compared to solids and liquids. In gases, atoms can move freely and collide with each other, leading to higher speeds.

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

Density formula: _____________________________

• Mass + Volume

• Mass / Volume

• Volume / Mass

• Mass x Volume

Answer explanation

The density formula is defined as mass divided by volume (Mass / Volume). This relationship shows how much mass is contained in a given volume, making it the correct choice.

Tools used to measure mass _____________________________

• Ruler

• Thermometer

• Balance

• Stopwatch

Answer explanation

The correct tool to measure mass is a balance, which compares the mass of an object against known masses. A ruler measures length, a thermometer measures temperature, and a stopwatch measures time.

James is observing different states of matter in his science class. Which model represents the atoms as a solid?

• A model showing atoms closely packed in a fixed position

• A model showing atoms moving freely and rapidly

• A model showing atoms sliding past each other

• A model showing atoms in a random arrangement with no movement

Answer explanation

The correct model represents atoms as closely packed in a fixed position, which is characteristic of solids. In solids, atoms vibrate but do not move freely, unlike in liquids or gases.

Which tool is commonly used to measure volume?

• Thermometer

• Ruler

• Graduated cylinder

• Stopwatch

Answer explanation

A graduated cylinder is specifically designed to measure the volume of liquids accurately, making it the correct choice. A thermometer measures temperature, a ruler measures length, and a stopwatch measures time.

What are atoms?

• Large visible particles

• Smallest unit of matter

• A type of chemical reaction

• A type of energy

Answer explanation

Atoms are the smallest unit of matter, making up all substances. They are not large visible particles, types of chemical reactions, or types of energy, which makes 'smallest unit of matter' the correct choice.

Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-5