Scientific Communication and Evolution of Chemistry

What is a nonmetal?

• An element that is generally a gas or a dull, brittle solid and is a poor conductor of heat and electricity

• An element that is shiny and a good conductor of heat and electricity

• An element that is always a liquid at room temperature

• An element that is a good conductor of electricity but not heat

Why does the formula unit of MgCl₂ contain one Mg²⁺ ion and two Cl⁻ ions?

• To balance the charge to zero

• To increase the mass

• To make it more reactive

• To change its color

What charge do ions in Group 16 typically have?

• 1+

• 2+

• 2−

• 3−

Which of the following elements is in Group 17 and forms a 1− ion?

• Na

• Be

• F

• N

Which of the following elements is likely to form a 1+ ion?

• Li

• Be

• N

• Cl

What do subscripts in a chemical formula represent?

• The total charge of the compound

• The number of ions of each element

• The order of elements

• The type of bond

What must the total charge of an ionic compound equal?

• One

• Two

• Zero

• Negative

From which group in the periodic table does potassium come?

• Group 1

• Group 2

• Group 16

• Group 17

What is the overall charge on one formula unit of an ionic compound?

• Positive

• Negative

• Zero

• Neutral

What is the charge of a calcium ion in an ionic compound?

• 1+

• 2+

• 1-

• 2-