Atoms & Matter

Which of the following statements about atomic structure is correct? Why?

• Atoms of different elements have varying numbers of neutrons. This is because the number of neutrons is determined by looking at the atomic number.

• The nucleus of an atom has no charge. This is because the charges of the protons and electrons cancel each other.

• Atoms have different elements have varying numbers of electron shells. This is because the number of electron shells is determined by looking at the atomic mass.

• The nucleus of an atom has a positive charge. This is true because it contains protons and neutrons.

Tags

NGSS.MS-PS1-1

Which of the following is a list of physical properties?

• color, state of matter, density

• temperature change when a substance is added,

  flammability, color

• density, conductivity, reacts with acid

• color, size, combustability

Gracie hasn't ridden her bike in a few years and has now decided to sell it at her mom's garage sale. When she gets the bike out from under her deck, she makes the following observations about the bike.

● The bike is rusted.

● The seat cover has a smooth texture.

● The front basket of the bike is purple.

Which of the following choices describes

the properties Gracie observed?

• Physical Properties: color, texture

  Chemical Properties: ability to rust

• Physical Properties: color, texture, ability

  to rust

  Chemical Properties: none

• Physical Properties: none

  Chemical Properties: color, texture,

  ability to rust

• Physical Properties: color, ability to rust

  Chemical Properties: texture

The melting of wax is a physical change, yet the buring of wax is a chemical change.

What is the most important difference between the physical change and chemical change of wax in a burning candle?

• Melted wax is a different phase of

  matter than solid wax.

• A higher temperature is needed to burn

  wax than to melt wax.

• The burning of wax forms new substances with different properties, while the melting of wax does not.

• Melted wax can be separated into other substances, while solid wax cannot.

Tags

NGSS.MS-PS1-2

True or false: The REACTIVITY of elements decreases from left to right on the periodic table.

• True

• False

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Carlos knows atoms of hydrogen (H) and

oxygen (O) can combine to make water.

He draws four possible models of a water

molecule. Based on the information from

the periodic table, which of his models is

correct?

• O---O---H

• O---H---O

• H---H---O

• H---O---H

Tags

NGSS.MS-PS1-1

Which of the following is a common sign that a chemical change has occurred?

• A chemical has become a different shape

• A chemical has turned a different color

• A chemical has changed size

• A chemical has changed to a different state (solid, liquid, or gas)

Tags

NGSS.MS-PS1-2

Water, also known as H 2O, cannot be

separated into hydrogen and oxygen.

Why?

• H₂O cannot be separated into hydrogen

  and oxygen because it is a physically

  combined compound.

• H₂O cannot be separated into hydrogen

  and oxygen because it is a chemically

  combined compound.

• H₂O cannot be separated into hydrogen

  and oxygen because it is a mixture that

  is chemically combined.

• H₂O cannot be separated into hydrogen

  and oxygen because it is a mixture that

  is physically combined.

Tags

NGSS.MS-PS1-1

What is VOLUME?

• A measure of how much matter is in an

  object; commonly measured by how

  much something weighs.

• is the relationship between the mass of

  the substance and how much space it

  takes up (volume); compactness

• the speed of an object

• the amount of space that an object

  takes up, or that is enclosed within a

  container

A student preforms an investigation to

determine the properties of an iron

nail. The list shows her findings.

o The nail can rust.

o The nail is denser than water.

o The nail is very hard.

o The nail can be bent.

• Density and hardness are chemical

  properties of iron.

• Rusting and bending are physical

  properties of iron.

• Rusting is a chemical property of iron.

• Hardness is a chemical property of iron.