On Target? Do this on your
Warm Up worksheet!
Solubility is explained by “Like dissolves like.” Explain
what this means and give an example.
For today
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Warmup
Finals and Grades
Solubility
Big ideas!
• Objective: I can explain how charges
influence the properties of our substances
with both words and pictures.
Review: Solubility
• “Like dissolves like”
– Solvation process
Why would salt conduct electricity in
water but NOT as a solid?
• Diamond white boarding!
• Think about:
1. What might be different about salt as a solid
crystal vs in a liquid?
2. What is salt able to do in water?
3. It can move around in water!
How can one substance dissolve in water and
NOT conduct electricity while another dissolves
and DOES conduct electricity?
• Think about:
1. How does the conductivity meter work? Does
it have charge?
2. How might particles be charged differently?
3. What needs to happen for electricity to be
conducted?
4. Why would deionized water not conduct
electricity?
How salt dissolves
How sugar dissolves
Big Ideas!
• In your notebook, fill in the following
sentences:
1. Charges are important because__________.
2. Water is attracted to both positive and
negative objects because______________.
3. Water can dissolve objects with charges
by____________.
4. Salt can conduct electricity in water
because_________. Sugar cannot conduct
electricity in water because__________.
SUMMARY
In a conductor, charged particles called
ions (+ or – charge) are moving in an
electrical current. For example, salt water
must have ions moving between the
prongs conducting electricity and so
completing the circuit, lighting the LED
lights.
Sugar in water is a insulator because ions
do not move so no electricity is conducted.
Notes: If it is blue write it
(or draw the diagram if the
blue is to sketch).
• Title: WHY SOLUTIONS CONDUCT
ELECTRICITY
Now think small….
Sketch this picture in your notebook.
See if you can label any of the parts.
EXPLORE: Particular Properties
Particle (Atom)
electron
negative(-)
neutron
neutral
proton
positive(+)
Do you think electricity is conducted
the same through a solution?
• What might be different about the atoms in
metals vs. solutions?
Ions-atoms with a positive or negative
charge
Electrolytes-substances that produce ions
in water
Example) Table salt (NaCl)
Summary questions
• What is the charge on unbonded atoms?
• The charge on unbonded atoms is _______
• Why does chlorine have a negative charge when
ionically bonded to sodium?
• Chlorine has a negative charge when ionically
bonded to sodium because
______________________
WHY DOES SALT NOT CONDUCT ELECTRICITY
AS A SOLID BUT DOES IN SOLUTION?
WHY DOES SALT NOT CONDUCT ELECTRICITY AS A
SOLID BUT DOES IN SOLUTION?
IONS CAN MOVE!!
How is that related to conducting
electricity?
To think about …
• How big is the nucleus of an atom compared
to the whole atom?
• Why don’t atoms pass through one
another?
• Why are you hovering 10 -8 cm above your
chair right now?
• WHY IS THIS IMPORTANT?
Attraction and repulsion:
One of the probes on conductivity meter is
positive while other is negative
• Opposite charges attract!
• Ions move in solution toward the opposite
charged probe
• (in salt water, Na+ moves toward –probe;
Cl- moves toward +probe)
• This movement conducts electricity!
Diagrams on pg. 112 - 13
1. Copy the picture of the conductivity meter in
the solution on page 112. What solution do
you think this is? What are the + ions and –
ions?
2. Label all the parts of the system.
3. Explain why the light is on in this picture.
4. Which figure on pg. 113 is water and which is
baby oil? Use evidence to explain your
answer.