T1L4 Checkpoint

Why do atoms form chemical bonds?

• To increase their energy
• To become more stable
• To become less stable
• To lose electrons

In an ionic bond, what happens to the electrons?

• They are shared equally
• They are transferred from one atom to another
• They disappear
• They stay with their original atoms

What is the chemical formula for sodium chloride (table salt)?

• NaCl
• NaCl2
• Na2Cl
• NaClO

How are covalent bonds formed?

• By transferring electrons
• By sharing electrons
• By losing protons
• By gaining neutrons

In a dot-and-cross diagram, what do the dots and crosses represent?

• Protons and neutrons
• Electrons from different atoms
• Positive and negative charges
• Nuclei and electron shells

What is a polar covalent bond?

• A bond where electrons are shared equally
• A bond where electrons are shared unequally
• A bond between two metal atoms
• A bond that only forms at the poles

Which of the following is a property of ionic compounds?

• Low melting point
• High electrical conductivity when solid
• Low solubility in water
• High melting point

What type of elements typically form ionic bonds?

• Two nonmetals
• Two metals
• A metal and a nonmetal
• Noble gases

Which of the following is a characteristic of covalent compounds?

• They always conduct electricity
• They have high melting points
• They are usually gases or liquids at room temperature
• They are always soluble in water

What is the correct chemical name for CaCl2?

• Calcium chloride
• Calcium dichloride
• Calciumdichloride
• Calcium(II) chloride