Unit 2 Quiz

What makes a chemical equation balanced?

• a. Equal numbers of molecules on each side

• b. Equal numbers of each type of atom on both sides

• c. Equal numbers of compounds on both sides

• d. Equal numbers of coefficients on both sides

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NGSS.MS-PS1-5

Which statement best describes the Law of Conservation of Mass?

• a. Mass can be created or destroyed during chemical reactions

• b. Mass is conserved only in physical changes

• c. The total mass of reactants equals the total mass of products

• d. Mass decreases during all chemical reactions

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NGSS.MS-PS1-5

In a balanced chemical equation, what must be equal on both sides?

• a. The number of molecules only

• b. The total mass only

• c. The number of atoms of each element

• d. The number of subscripts

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NGSS.MS-PS1-5

In the equation 2H₂​+O_2​→2H₂​O, how many oxygen atoms are on the reactant side?

• 1

• 2

• 3

• 4

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NGSS.MS-PS1-1

Which equation is already balanced?

• Na + Cl₂ --> NaCl

• 2Na + Cl₂ --> 2NaCl

• Na + 2Cl --> NaCl

• 2Na + Cl --> 2NaCl

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NGSS.MS-PS1-5

How many hydrogen atoms are in 3H₂SO₄​  ?

• 3

• 4

• 6

• 12

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NGSS.MS-PS1-1

The mineral albite is composed of four elements and has the chemical formula NaAlSi₃O_8. Which of these elements does albite contain?

• A. Astatinte

• B. Sulfur

• C. Nitrogen

• D. Aluminum

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

In the equation CaCO₃​→CaO+CO₂​, how many oxygen atoms are on the product side?

• 2

• 3

• 4

• 5

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NGSS.MS-PS1-1

NGSS.MS-PS1-5

What does a coefficient in front of a chemical formula indicate?

• a. The atomic number of the elements

• b. The number of atoms in the molecule

• c. The number of molecules or formula units

• d. The charge of the compound

Which equation represents a balanced chemical reaction?

• Cu + O₂ --> CuO

• 2Cu + O₂ --> 2CuO

• Cu + O₂ --> Cu₂O

• Cu + O --> 2CuO

Tags

NGSS.MS-PS1-5