Unit 1 Review - Missed Questions

A precipitate is a 

• liquid that forms when two solids are reacted
• a solid that forms when two liquids are mixed
• a gas that forms when vinegar and baking soda react
• a change of color in a solution

Tags

NGSS.MS-PS1-2

What does the Law of Conservation of mass state?

• Mass is created in a chemical reaction
• Mass is created in a physical change
• New chemicals formed from a chemical reaction have a larger overall mass than the original reactants
• Mass is never created or destroyed

Tags

NGSS.MS-PS1-5

Does the equation H₂+O₂ →H₂O follow the Law of Conservation of Mass?

• Yes, because the atoms are equal.

• No, because more info is needed.

• No, because there are more atoms in the product.

• No, because there are more atoms in the reactant.

Tags

NGSS.MS-PS1-5

A pure substance made of one kind of atom that cannot be broken down chemically into simpler substances.

• Element

• Compound

• Atom

• Molecule

A student drops a rock and a cork in a cup of water as shown.

The student observes that the cork floats while the rock sinks in water. What can be concluded from the observation?

• The cork is more dense than the rock and water

• The rock is more dense than the cork and water

• The rock is more dense than the cork but less dense than the water

• The cork is more dense than the water but less dense than the rock

The number to the lower side of an element is a 

• Subscript
• Superscript
• Coefficient
• Charge

When sodium (Na) and chlorine (Cl) combine to form sodium chloride (NaCl), sodium chloride is the:

• Originator

• Reactant

• Product

• Arrow

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

How many atoms do you have in the compound 2MgCl₂?

• 2 atoms

• 4 atoms

• 6 atoms

• 8 atoms

Tags

NGSS.MS-PS1-1

Law of conservation of mass states the amounts of atoms in the reactants and the products...

• Increase

• Decrease

• Stay the same

• No correct answer

Tags

NGSS.MS-PS1-5

Which of the following is evidence of a chemical change? (Select all that apply)

• Precipitate

• Temperature change

• Shape change

• Light given off

• Gas formed

Tags

NGSS.MS-PS1-2