Rust is a compound with the formula Fe2O3. What elements combine to form rust?

• iron and water

• iron and oxygen

• iron and air

• iron and acid

Tags

NGSS.MS-PS1-1

What number and types of atoms occur in a formula unit of Ca(NO3)2?

• 1 carbon atom, 1 neon atom, and 6 oxygen atoms
  

• 1 calcium atom, 2 neon atoms, and 3 oxygen atoms

• 1 carbon atom, 1 nitrogen atom, and 3 oxygen atoms

• 1 calcium atom, 2 nitrogen atoms, and 6 oxygen atoms

Tags

NGSS.MS-PS1-1

How many atoms are in one formula unit of the compound FeC5O5?

• 5

• 11

• 15

• 26

Tags

NGSS.MS-PS1-1

How many atoms of carbon are included in one formula unit of the compound Na2C2O4?

• 2

• 4

• 6

• 8

Tags

NGSS.MS-PS1-1

The compound potassium sulfate, K2SO4, is composed of

• 2 atoms of potassium, 1 atom of sulfur, and 4 atoms of oxygen.

• 2 atoms of potassium, 4 atoms of sulfur, and 4 atoms of oxygen.

• two molecules of potassium and one molecule of sulfate.

• one molecule of potassium and two molecules of sulfate.

Tags

NGSS.MS-PS1-1

How many atoms are in one formula unit of magnesium hydroxide, Mg(OH)2?

• 3

• 4

• 5

• 6

Tags

NGSS.MS-PS1-1

The chemical formula for water is H20. What does the formula show about each element in the compound?

• the number of valence electrons

• the charge of the compound

• the mass of protons in each atom

• the number of atoms of each element

Tags

NGSS.MS-PS1-1

The periodic table provides information about the atoms of different elements . Which is a characteristic of an atom determines what element it is?

• number of neutrons

• number of protons

• state of matter

• atomic mass

In the late 1700s, Antoine Lavoisier performed a series of experiments to find out what happened when a substance burned. In each experiment, he observed that the weight of the container and its contents was the same at the end of the experiment as the beginning. These observations led him to propose the law of

• combustion.

• fixed proportions.

• conservation of mass.

• conservation of energy.

Tags

NGSS.MS-PS1-5

A science class is studying the states of matter. One group of students freezes 100 grams (g) of water in a cup. Another group of students melts 50g of ice in a cup. Which of these will most likely occur at the end of the experiment?

• The temperature of both cups will be the same.

• Both samples in the cups will be in the same state.

• Both groups will have the same mass with which they started.

• The time required for the changes in states of matter will be the same.

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4