Crystal Formation of Sodium Borate Na2B4O7 (Borax) 11-30-16

11/30 No Opener Paste methods into your notebook

Pre-lab questions Sodium Borate is a salt with the formula Na2B4O7. List the ions and their charges that make up this salt. Draw a picture of a beaker with water. Then draw what will happen when sodium borate dissolves in the water.

Purpose Sodium Borate is a salt (ionic compound) with a formula unit of Na2B4O7. In this lab we will: dissolve it into water to create an aqueous solution heat the solution so that more salt will dissolve soak an object in the solution and finally, allow the object to cool overnight so that the salt will crystallize on our object

Materials string / wood splint 400mL Beaker (or other large beaker) pipe cleaner Sodium Borate boiling water food coloring (opt.) scissors hot plate goggles

Procedures 1. Cut a pipe cleaner into three equal sections. 2. Twist the sections together at their centers to form a six-sided snowflake shape. Use your creativity with the shape…just make sure that it will fit in the beaker. 3. Tie the string to the end of one of the ornament arms. Tie the other end of the string to a wood splint. You want the length to be such that the splint hangs the snowflake into the jar and well under solution. 4. Boil ~250mL of water 5. Use a scoop to add sodium borate, stirring to dissolve after each addition. The solution should look a little cloudy….too much salt is not good. 6. If desired, you may tint the solution with food color. 7. Hang the ornament into the beaker so that the wood splint rests on top of the jar and the ornament is completely covered with liquid and hangs freely (not touching the bottom of the jar). 8. Allow the jar to sit in an undisturbed location overnight. 9. Sketch the result as your observations….note the structure of the crystals

Sketch Create a sketch of your ornament. Sketch an example of the shape of a crystal that has formed. There are many possible shapes, but predictable forms for each salt.

Common Na2B4O7 Crystal Types Prism Bipyramid Hexagon Bi

Borax Crystal Lab Prism Bipyramid Hexagon Pre Lab Materials Procedure Sodium Borate is a salt with the formula Na2B4O7. List the ions and their charges that make up this salt. Draw a picture of a beaker with water. Then draw what will happen when sodium borate dissolves in the water Materials string / wood splint 400mL+ Beaker (share with a partner) pipe cleaner (1 per person) Sodium Borate boiling water food coloring (optional) scissors hot plate goggles (not optional) Post Lab Sketch the result as your observations note the structure of the crystals Procedure Use 1 pipe cleaner to make an object Tie the string onto the object and loop around popsicle stick. Make sure that your object doesn’t touch the sides or bottom!!! Boil enough water to cover your suspended ornaments. ~250ml Scoop borax into your boiling solution, stirring until all salt is dissolved before adding another scoop. BE PATIENT  The solution should look a little cloudy with a small amount of undissolved salt. If desired tint your solution (check with your partner first! Hang the object into the beaker so that it is completely covered with liquid and hangs freely (not touching the bottom of the jar). Allow the jar to sit in an undisturbed location overnight. Make observations for post lab. Prism Bipyramid Hexagon

Borax Crystal Lab Prism Bipyramid Hexagon Pre Lab Materials Procedure Sodium Borate is a salt with the formula Na2B4O7. List the ions and their charges that make up this salt. Draw a picture of a beaker with water. Then draw what will happen when sodium borate dissolves in the water Materials string / wood splint 400mL+ Beaker (share with a partner) pipe cleaner (1 per person) Sodium Borate boiling water food coloring (optional) scissors hot plate goggles (not optional) Post Lab Sketch the result as your observations note the structure of the crystals Procedure Use 1 pipe cleaner to make an object Tie the string onto the object and loop around popsicle stick. Make sure that your object doesn’t touch the sides or bottom!!! Boil enough water to cover your suspended ornaments. ~250ml Scoop borax into your boiling solution, stirring until all salt is dissolved before adding another scoop. BE PATIENT  The solution should look a little cloudy with a small amount of undissolved salt. If desired tint your solution (check with your partner first! Hang the object into the beaker so that it is completely covered with liquid and hangs freely (not touching the bottom of the jar). Allow the jar to sit in an undisturbed location overnight. Make observations for post lab. Prism Bipyramid Hexagon