Chemistry Semester 1 Exam Review

In the equation,          2Mg + O₂ ---> 2MgO, which are the reactants?

• Mg and O
• MgO
• Mg and MgO
• O and MgO

Balance this equation, Ca + H₂O --> CaO + H₂

• Ca + 2H₂O --> CaO + 2H₂
• 2Ca + H₂O --> CaO + H₂
• Its balanced as it is
• Cannot be balanced

Which of the following describes covalent bonds? Select all that apply. 

• lower energy state and higher stability

• occur between atoms of similar electronegativity

• involve the sharing of electrons

• occur between atoms with a large electronegativity different

What type of chemical reaction is this one?
Al(OH)₃ --> Al2O3  + H2O

• Decomposition
• Combustion
• Synthesis
• Single Replacement 

What coefficients are needed to correctly balance the equation?
_Bi   +   _O₂   >   _Bi₂O₃

• 3,2,3
• 2,3,2
• 4,3,2
• none of these

How many VALENCE ELECTRONS does Chlorine have?

• 2

• 7

• 8

• 10

• 17

Ionic bonds are formed when electrons get

• Shared between two atoms

• Removed from both atoms

• Transferred from one atom to another

• Added to both atoms

Ionic bonds typically form between

• A metal and a nonmetal

• Two nonmetals

• Two metals

• A metalloid and a metal

What is the correct formula for Sodium Chloride?

• SCl

• NaCl

• SC

• NaCl₂

Cations _______ electrons, becoming _______ charged.

• Gain; positively (+)

• Gain; negatively (-)

• Lose; positively (+)

• Lose; negatively (-)