hydrates

What is the empirical formula for the following:
32.40% sodium, 22.5% sulfur; 45.1 % oxygen, 37.75% water?

• Na₂SO₄H₆O₃
• Na₂SO_{4 .} 2H₂O
• Na₂SO_{4 .} 3H₂O
• Na₂SO_{4 .} (H₂O)₃

Tags

NGSS.HS-PS1-7

Na₂CO₃ · 10H₂O is known as sodium sulfate ______

• Hydroxide
• Hydrate
• Decahydrate
• None of the above

A 15.67 g sample of a hydrate of magnesium carbonate was heated to drive off the water. The mass was reduced to 7.58 g. What is the formula of the hydrate?

• MgCO₃ · 5H₂O
• MgCO₃ · 4H₂O
• MgCO₃ · 6H₂O
• MgCO₃ · 1H₂O

Tags

NGSS.HS-PS1-7

A hydrate of magnesium chloride is present and the following data is collected:
mass of crucible = 22.130 grams
mass of crucible + hydrate = 25.290 grams
mass of crucible and contents after heating = 23.491 grams
What is the complete formula of this hydrate?

• MgCl₂ · 12H₂O
• MgCl₂ · 11H₂O
• MgCl₂ · 6H₂O
• MgCl₂ · 13H₂O

Tags

NGSS.HS-PS1-7

Name the following ionic compound: MgSO₄*7H₂O

• magnesium sulfate * hexahydarte
• magnesium sulfate hexahydarte
• magnesium sulfate heptahydrate
• magnesium sulfate* heptahydrate

The hydrate of barium chloride is 85.3% anhydrous material. How many moles of hydration does this compound contain?

• 1

• 2

• 3

• 4

When 1.75 grams of a calcium chloride hydrate sample is heated the mass is reduced to 0.890 grams. How many waters of hydration are attached to each crystal?

• 2

• 4

• 5

• 6

The percent water in a lithium bromide hydrate is 29.3 %. Calculate the waters of hydration

• 2

• 4

• 5

• 6

A compound that attracts and holds water in the structure forming a crystalline substance is called a(n)

• anhydrous material

• hydrate

• electrolyte

• alloy

In the performance of the copper II sulfate hydrate lab a visual indicator that water was still present was

• the substance was blue

• the substance turned white

• the substance fizzed

• the substance changed temperature

Tags

NGSS.MS-PS1-2