empirical, molecular, hydrrates

Name the following ionic compound: MgSO₄*7H₂O

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

Name the following hydrate:  NaCl * 5H₂O

• sodium chloride 
• sodium monochloride pentahydrate
• sodium chloride pentahydrate
• pentahydrate

What is the correct chemical formula for barium hydroxide octahydrate?

• Ba(OH)₂ . 8H₂O

• Ba(OH)₂ . H₂O

• 8Ba(OH)₂ . H₂O

• Ba . 8(OH)₂

What is the best method for removing water from a hydrated compound?

• freezing

• filtration

• distillation

• heating

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 evaporating dish = 22.130 grams

mass of dish + hydrate = 25.290 grams

mass of dish and contents after heating = 23.491 grams

What is the mass of the anhydrous MgCl₂?

• 1.799 g

• 3.160 g

• 1.361 g

• 23.491 g

Tags

NGSS.HS-PS1-7

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

If 15.6 g of hydrate are heated and only 11.7 g of anhydrous salt remain, calculate the % of water lost.

• 25.9%
• 19.2%
• 37.9%
• 76.3%

Crucible, cover: 19.8 g
Crucible, cover, and hydrate: 23.0g
Crucible, cover, and salt: 21.5g
Calculate % of water lost.

• 90.0%
• 46.9%
• 39.3%
• 45.5%

What is the empirical formula of the following molecular formula:  C₃H₆

• C₃H₆
• CH₂
• C₂H₄
• CH₃