Chemical Equations

How many Sodium (Na) are in 6NaCl?

• 1
• 12
• 6

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

• 3
• 6
• 12
• 24

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.
_CF₄ + _Br₂ -- _CBr₄ + _F₂

• 2,1,2,1
• 1,2,2,1
• 1,2,1,2
• 2,2,2,2

Balance this equation.
_CH₄ + _O₂ --> _CO₂ + _H₂O

• 1,2,1,1
• 2,1,2,1
• 1,2,1,2
• 0,2,0,2

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.
  

Which one is a compound?

• Co
• Br
• Fe
• CO

Which one is an element?

• Co
• CO
• CO₂
• CO₃^-2

How many different elements are found in the following molecule? Mg(ClO₃)₂

• 1

• 4

• 3

• 5

Which of the following equations are correctly balanced?

• 12CO₂ + H₂O ---> C₆H₁₂O₆ + O₂

• CO₂ + H₂O ---> 3C₆H₁₂O₆ + O₂

• CO₂ + 9H₂O ---> C₆H₁₂O₆ + O₂

• 6CO₂ + 6H₂O ---> C₆H₁₂O₆ + 6O₂