Experimentally know the electrically conductive properties of elements we have in everyday life.
Develop these Key Competencies:
- Problem Solving
- System Thinking
- 1 container.
- 2 wooden sticks.
- Aluminum foil.
- Insulating tape.
- 1 LED bulb.
- 3 wires with crocodile clips.
- 1 battery holder
- 2 AA batteries
Add the batteries to the battery holder.
Connect with an alligator wire to one end of the LED spotlight and to one of the wires of the battery holder (check the polarity of the post of the spotlight you are connecting it to).
Wrap 2 popsicle wooden sticks with aluminum foil and electrical tape.
Connect the excess end of the buzzer to one of the sticks with an alligator wirecable with crocodile clip.
Take another wire and connect the battery holder to another stick.
Insert the sticks into the container of salt water and turn on the battery holder. The LED bulb should light up.
You must turn on the spotlight
Salts dissolved in water break down into positively and negatively charged ions. Conductivity is defined as the ability of water to conduct an electric current through dissolved ions. The most positive ions are sodium (Na+), calcium (Ca+2), potassium (K+) and magnesium (Mg+2). The most negative ions are chloride (Cl-), sulfate (SO4-2), carbonate, bicarbonate. Nitrates and phosphates do not contribute appreciably to conductivity, although they are very important biologically.
Salinity is a measure of the amount of salts dissolved in water. Salinity and conductivity are related because the amount of dissolved ions increases the values of both. Salts in the sea are mainly sodium chloride (NaCl). However, other saline waters, such as those of Mono Lake, have elevated salinity due to a combination of dissolved ions such as sodium, chloride, carbonate, and sulfate.
Did you know…
One of the processes to get the salt from the sea to your home is by drying the salt water with the sun's energy.
Relevant information if you are facilitating