Empirical, Molecular, Percent Comp and Hydrates Lab Quiz

Find the percentage composition of  Mg in Mg₃(PO₄)₂.
   

• 27.75% Mg
• 23.57% Mg
• 48.68% Mg
• 13.45% Mg

Tags

NGSS.HS-PS1-7

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 · 7H₂O
• MgCl₂ · 11H₂O
• MgCl₂ · 6H₂O
• MgCl₂ · 13H₂O

Tags

NGSS.HS-PS1-7

Name the following ionic compound: MgSO₄*7H₂O

• magnesium sulfate * sexahydarte

• magnesium sulfate hexahydarte

• magnesium sulfate heptahydrate

• magnesium sulfate septahydrate

An empirical formula:

• is a formula that calculates the coefficients of a compound in a balanced equation.
• is the simplest whole-number ratio of moles of elements in the compound.

A 4.175 gram sample of a certain hydrate of copper (II) sulfate, CuSO4•xH2O, is heated until all the water is driven off. The resulting anhydrous compound weighs 3.120 grams. What is the formula of the hydrate?

• CuSO4•H2O

• CuSO4•3H2O

• CuSO4•6H2O

• CuSO4•4H2O

Tags

NGSS.HS-PS1-7

A sample with a molar mass of 34.00 g/mol is found to consist of 0.44 g H and 6.92 g O. Find its molecular formula.

• HO

• H₂O₂

• H₂O

• H_1/2O_1/2

Tags

NGSS.HS-PS1-7

KCl ⋅ 3H₂O

• potassium chloride trihydrate
• potassium trichlorate
• potassium (I) three water
• potassium (I) trichlorate

Determine the formula of CuSO₄·?H₂O hydrate given the following data:

Test Tube = 23.56 g

Test Tube + Hydrate = 26.06 g

Test Tube + Anhydrate = 25.16 g

• CuSO₄·H₂O

• CuSO₄·2H₂O

• CuSO₄·4H₂O

• CuSO₄·5H₂O

Tags

NGSS.HS-PS1-7

Which pair has the same empirical formula?

• NaCrO₄ and Na₂Cr₂O₇
• C₂H₄O₂ and C₆H₁₂O₆
• C₃H₆O₃ and C₂H₆O₂
• CH₄ and C₂H₆