Chemistry Review

A subscript is the small number below a(n) ________ that tells the number of _______ of that element.

• element symbol; atoms
• atom; element symbol
• subscript; protons
• compound; elements

If there is no subscript, there is ______ atom(s) of that element.

• 0
• 2
• 1
• no

How many elements are present in the compound Mg₂As₃COHNi₂?

• 10
• 7
• 6
• 9

Which of these is NOT a compound?

• H₂Cr
• 2Cr₃
• OH
• PNi

Which is the correct formula for:
three hydrogen (H)
one sulfur (S)
four oxygen (O)

• H₃SO₄
• HSO₄
• H₄S₃O
• H₂O

How many Sodium (Na) are in 6NaCl?

• 1
• 12
• 6
• 2

How many Aluminum are in Al₂O₃?

• 3
• 2
• 5
• 6

2H₂O → 2H₂ + O₂; What are the products?

• →
• 2H₂O
• 2H₂ + O₂
• O₂

2H₂O → 2H₂ + O₂; What are the reactants?

• →
• 2H₂O
• 2H₂ +O₂
• 2H₂

Which equation obeys the law of conservation of mass?

• H₂ + O₂ → H₂0
• C + 2H₂ → CH₄
• 2Fe₂O₃ → 2O₂ + 4Fe
• K(OH)₃ + 2Na → 3KH + Na₂O