STAAR Science 2024

Based on these properties, which element is most likely a nonmetal?

• Element 1

• Element 2

• Element 3

• Element 4

Answer explanation

Element 2 is most likely a nonmetal due to its properties, which typically include being poor conductors of heat and electricity, having lower melting and boiling points, and existing in various states at room temperature.

Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-2

Which statements correctly compare metals and nonmetals?

• Metals tend to be good conductors of thermal energy. Nonmetals tend to be good insulators of thermal energy.

• Metals are dull and brittle. Nonmetals are shiny and malleable.

• Metals are good insulators of electricity. Nonmetals tend to be good conductors of electricity.

• Metals cannot be stretched into thin wires. Nonmetals can be stretched into thin wires.

Answer explanation

Statement F correctly highlights that metals are typically good conductors of heat and electricity, while nonmetals are not. This fundamental difference is key in comparing the two categories of elements.

Tags

NGSS.MS-PS3-3

A clear liquid from a flask is poured into another clear liquid in a beaker. Which of the following results of this procedure would indicate a new substance was formed?

• The level of the substance in the beaker is higher after the other liquid is added.

• A yellow solid forms and then settles to the bottom of the beaker.

• Small white crystals are left behind in the flask that held the first liquid.

Answer explanation

A yellow solid forming and settling indicates a chemical reaction occurred, producing a new substance. The other options do not confirm the formation of a new substance.

Tags

NGSS.MS-PS1-2

A student is trying to classify an unidentified, solid gray material as a metal or a nonmetal. Which question will best help the student classify the material?

• F Is the material malleable or ductile?

• G Does the material feel hard to the touch?

• H Will the material float in water?

• J Does the material feel rough or smooth?

Answer explanation

To classify the material, the best question is whether it conducts electricity. Metals typically conduct electricity well, while nonmetals do not. Therefore, asking about electrical conductivity will help determine its classification.

What is the primary function of the chloroplasts in plant cells?

• To break down sugar molecules to release energy

• To store water and nutrients

• To capture light energy and convert it into chemical energy

• To control the entry and exit of substances in and out of the cell

Tags

NGSS.MS-LS1-6

What is the term for the movement of particles from an area of higher concentration to an area of lower concentration?

• Osmosis

• Diffusion

• Active transport

• Endocytosis

Which of the following is NOT a renewable resource?

• Solar energy

• Wind energy

• Coal

• Hydroelectric power

What is the term for the amount of matter in an object?

• Weight

• Density

• Mass

• Volume

Tags

NGSS.MS-PS1-1

Which of the following is a chemical change?

• Dissolving salt in water

• Boiling water

• Burning wood

• Melting ice

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

What type of symbiotic relationship benefits one organism without harming the other?

• Mutualism

• Commensalism

• Parasitism

• Predation