Solutions and Solubility Review: Extra Credit

Heart cells require a certain balance of sodium and potassium ions to function. The blood, which is approximately 83% water, carries these two types of ions to the heart. The property of water that allows it to carry ions to the heart is its—

• molecular mass

• specific heat

• polarity

• density

Which compound in this reaction is the precipitate?

3CaCl₂ + 2Na₂PO₄ --> 6NaCl + Ca₃(PO₄)₂

• CaCl₂

• Ca₃(PO₄)₂

• Na₂PO₄

• NaCl

Upon completion of a lab exercise, students examine the above data table. Which of the following conclusions is supported by this data?

• CaCl₂ is insoluble

• NaCl is insoluble

• Mg₂CO₃ is soluble

• NaCl is more soluble than CaCl₂

If a student wanted to make 350. mL of a 1.56 M solution of NaCl, how many grams of sodium chloride would they need to use?

• 9.34 g

• 31.9 g

• 224 g

• 546

A student made a 2.00 L solution using 86.3 g of sodium chloride. What is the molarity of the solution that the student made?

• 0.200 M

• 0.738 M

• 1.47 M

• 4.82 M

A solution is made using 32.0 g NaCl and 350. mL of water. What is the concentration of this solution?

• 1.56 M

• 5.34 M

• 192 M

• 655 M

Students working in lab use 52.3g of CaCl₂ to make a solution. When the solution is brought to a final volume of 800. mL, what is the concentration?

• 0.139 M

• 0.153 M

• 5.88 M

• 0.632 M

A lab technician is called on to prepare 2.0L of a .9M saline solution. The lab has 2L beakers in stock. What steps must she follow to fill the order?

• Add 116.9g of NaCl to 2.0L of water, stir until dissolved, then pour out any solution in excess of 2.0L.

• Measure 105.2g of NaCl, pit it into the beaker, add enough distilled water to make 2.0L, and stir until dissolved.

• Measure 58.4g of NaCl, add it to 2.0L of H2O already in the beaker, stir until dissolved

• Pour tap water into the beaker until full, add 9.0g of table salt, then stir until dissolved.

Tags

NGSS.MS-PS1-1

A teacher is making diluted solutions for the lab. The stock solution is 200mL of 5M HCl. What volume will the teacher need to obtain a 2M solution?

• 30 mL

• 80 mL

• 100 mL

• 500 mL

When 50 mL of a 2M HNO₃ solution is diluted to 200 mL of HNO₃, what is the resulting molarity?

• 0.5 M

• 1.0 M

• 2.0 M

• 6.0 M