Salt crystallization and laboratory norms

What equipement is used for a chemistry filtration?

• A conical flask, a beaker, a tripod

• A funnel, a filter paper, a conical flask

• A funnel, a tripod and a glass rod

• An evaporating dish, a beaker and a funnel

Why do we keep adding salt and stirring until it doesn't dissolve anymore, in the first step of the experiment?

• To make sure all salt is dissolved

• To keep the solution unsaturated

• To reach saturation

• To help the salt diffuse in water

If we can dissolve at most 10 g of salt in 20 mL of water at 27 C (until it reaches saturation), the solubility of salt at 27 C is...

• 10 g per 100 mL of water

• 50 g per 100 mL of water

• 10 g per 1 L of water

• 50 g per 1 L of water

In our experiment, we didn't heat up the salt solution. If we heat up the solution, can we dissolve more or less salt than if we keep it at room temperature (25 C) ?

• It depends on how much we stir the solution

• Dissolve less

• Dissolve more

• I don't know

Safety rules:

In the laboratory, what is allowed to do?

• Play and run around

• Bring food or drinks

• Throw things to other students

• Clean the equipement after the experiment

What should you do if you break some glassware?

• Hide it under the table

• Clean the broken glassware with your hands

• Ask the instructor what to do

• Don't tell anyone

When do you need to check on your salt crystals after your experiment is finished, to write down your observations?

• next Monday

• next Friday

• after 3 days

• every day

What shape do you expect your salt crystals to have after water evaporates?

• round shape

• cubic shape

• any shape

• flat shape

What is the chemical formula and the bonding in our salt crystals?

• NaCl,

  covalent bonding

• KCl,

  ionic bonding

• NaCl,

  Ionic bonding

• Na,

  metallic bonding

How did you find this chemistry experiment?

• Interesting

• Interesting but too easy

• Not interesting

• Not interesting and too hard