Test 2 Review

Which of the following describes the subatomic particles correctly?

• Neutrons have no charge

• Electrons are inside the nucleus.

• Electrons have a positive charge.

• Neutrons are larger than protons.

Where are protons in an atomic model?

• Inside the nucleus

• Between the orbitals

• On the orbitals

• In the golgi apparatus

Tags

NGSS.MS-PS1-1

You have a beaker of sand, water, and salt. How would you classify this substance?

• Homogeneous Mixture

• Heterogeneous Mixture

• Element

• Compound

Answer explanation

It is made of different substances physically combined, making it a mixture. You would be able to see the different parts, making it heterogeneous.

You have a beaker of salt dissolved in water. How would you classify this substance?

• Homogeneous Mixture

• Heterogeneous Mixture

• Compound

• Element

Answer explanation

Dissolving is a way of physically mixing two substances. You can't see the different parts, so it is homogeneous.

10 grams of methane reacts with 10 grams of oxygen to form 5 grams of carbon dioxide and 15 grams of water. Does this reaction follow the Law of Conservation of Mass?

• No

• Not enough information

• Yes

• No reaction has occurred

Answer explanation

The reactants (oxygen and methane) add up to 20g. The products (carbon dioxide and water) also add up to 20g.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

How would this substance be classified?

• Homogeneous Mixture

• Heterogeneous Mixture

• Compound Molecule

• Elemental Molecule

Answer explanation

This molecule is made of two elements bonded together, so it is a compound.

Tags

NGSS.MS-PS1-1

How would this substance be classified?

• Homogeneous Mixture

• Heterogeneous Mixture

• Compound Molecule

• Elemental Molecule

Answer explanation

This molecule is made of one element bonded together, so it is an elemental molecule.

Tags

NGSS.MS-PS1-1

Which elements are poor conductors of heat and electricity?

• Metals

• Nonmetals

• Metalloids

• Rare Earth Metals

Tags

NGSS.MS-PS3-3

Which of the following has the lowest kinetic energy?

• Solid

• Liquid

• Gas

• Condensation

Answer explanation

Kinetic energy is the energy of movement. Movement is lowest in solids, which vibrate in place.

Tags

NGSS.MS-PS3-1

Which of the following has the lowest intermolecular force?

• Solid

• Liquid

• Gas

• Condensation

Answer explanation

Intermolecular force is the attraction between molecules. In a gas, molecules are very spread out, so attraction between the molecules is low.