Q1 Chem Exam Review

Which of the following is a chemical change?

• cooking an egg

• shredding paper

• microwaving a bowl of soup

• water changes state in the water cycle

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

A student puts an ice cube into a beaker and allows it to melt. Which of the following statements best describes what happens to the water molecules during this investigation?

• The molecules move apart until the entire beaker is filled

• The molecules move apart until they are no longer touching each other

• The molecules become randomly arranged and can slide past each other

• The molecules become arranged in a pattern and maintain fixed positions

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NGSS.MS-PS1-4

Which of the following statements describes a difference between a chemical change and a physical change in a substance?

• A physical change occurs only in elements; a chemical change occurs only in compounds

• A chemical change occurs only in elements; a physical change occurs only in compounds

• The result of a physical change is a different composition; in a chemical change, the composition remains the same

• The result of a chemical change is a different composition; in a physical change, the composition remains the same

Particles of which of the following substance are farthest apart at room temperature?

• Solid

• Liquid

• Gas

• Plasma

The average distance between molecules always increases during which of the following phase changes?

• Gas to Solid

• Liquid to Gas

• Gas to Liquid

• Liquid to Solid

Tags

NGSS.MS-PS1-4

Which of the following statements explains why oxygen is classified as a pure substance and air is classified as a mixture?

• Oxygen is more reactive than air

• Oxygen has a higher density than air

• Oxygen undergoes phase changes, whereas air is always a gas

• Oxygen contains only one type of atom, but air contains several different atoms

Tags

NGSS.MS-PS1-1

A student made a homogeneous mixture of water and salt. Which of the following statements applies to this homogeneous mixture?

• This mixture is the same throughout

• This mixture is a pure substance

• The salt is not evenly distributed throughout this mixture

• The salt chemically combines with the water in this mixture

If you cut a wooden block in half, each half would have

• Half the density of the original piece

• Twice the density of the original piece

• The same density as the original piece

• No density at all

The density of an object is

• The mass divided by the volume, D = m/v

• The volume divided by the mass, D = v/m

• The same as its weight

• The same as the size of the object

When water freezes, liquid water turns to solid ice mainly because

• The water molecules get harder

• The molecules move slowly enough that their attractions keep them in fixed positions

• All liquid water eventually becomes ice

• Ice can float on water

Tags

NGSS.MS-PS1-4