Lessons 1 Chemical Equation Review

In chemical reactions, what does the principle of conservation of mass mean?

• Matter is not created or destroyed.
• The total mass of the reactants is greater than the total mass of the products.
• The total mass of the reactants is less than the total mass of the products.
• Matter is not changed.
  

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NGSS.MS-PS1-5

How many Hydrogen (H) atoms are in NH₃O5

• 3
• 4
• 5
• 1

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NGSS.MS-PS1-1

Which of the following shows the correct way to balance the chemical equation?

__Fe + __O₂ ->___ Fe₂O₃

• 4Fe + 3O₂ -> 2Fe₂O₃

• 2 Fe + 3O₂ -> Fe₂O₆

• 4 Fe + O₆ -> 2Fe₂O₃

• None of the options are correctly balanced.

Balance this equation...

__HgO --> ___Hg + O₂

• It is balanced

• 2HgO --> Hg + O₂

• 2HgO --> 2Hg + O₂

How many HCl molecules do you need to balance this equation? 
Mg +  __HCl --->  MgCl₂ + H₂

• 1
• 2
• 3
• 4

Tags

NGSS.MS-PS1-5

Balance this equation
_Al +_HCl --> _H₂ +_AlCl₃

• 2, 6, 3, 2
• it is already balanced
• 4, 12, 3, 4
• 2, 1, 4, 5

Tags

NGSS.MS-PS1-5

How many atoms of carbon (C) are in C₆H₁₂O₆?

• 3
• 6
• 12
• 24

Tags

NGSS.MS-PS1-1

How many atoms are there TOTAL in:
H₂SO₄

• 6
• 5
• 7
• 3

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NGSS.MS-PS1-1

All of the following reactions are correctly balanced except-

• A
• B
• C
• D

Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-5