Week 4
Task 1 Review of Laboratory Equipment and Safety
Science Aspects 1 Focus 1.2, page 6 Review of Laboratory equipment and Safety
Read through pages 6 to 8
Draw the scientific drawing shown in Figure 1.2.4 on page 8
Read through pages 6 to 8
- Write the Subheading Laboratory Rules
- Write the Subheading Laboratory equipment
- Write the Subheading Sketching Laboratory equipment
Draw the scientific drawing shown in Figure 1.2.4 on page 8
Task 2 Thinking Science Lesson 2: Two Variables
In our Salt Investigation we have been working with variables.
Relationship
As the value of the independent variable increases what happens to the value of the dependent variable?
- Recall what the term variable means.
- What does the term value mean?
- Which is the Independent variable? Why did you choose this?
- How are we measuring the value of the Independent variable?
- Which is the Dependent variable? Why did you choose this?
- How are we measuring the value of the Dependent variable?
Relationship
As the value of the independent variable increases what happens to the value of the dependent variable?
Task 3 Lighting the Bunsen Burner
Science Aspects 1 page 9
- Draw and label the Bunsen Burner.
- Remove the barrel from your burner and draw the gas jet inside.
- Unclog the jet if necessary.
- Recall the burner safety rules.
- Follow the rules to light the burner. One read, one light and then swap roles.
- Use the luminous flame to heat 100mL water in a beaker. What do you observe forming on the base of the beaker? Suggest reasons for this.
- Now measure 100mL water into a beaker. Set up a thermometer to measure the boiling temperature of water. Record your group results
Task 4 Investigation: The Effect of Increasing salt concentration on boiling point
Use the laboratory equipment to investigate the effect of increasing salt concentration on boiling point.
You will set this up this investigation as a Fair Test where you;
From your boiling point data you can calculate the salt concentration of sea water.
The measurements below are the salt concentrations in a unit called milliSiemens. It is a measure of electrical conductivity. (Salt solutions conduct electricity.)
Calibrate your sea concentration to the salt concentration below.
Now convert the values for salt concentrations in milliSiemens into % concentrations.
You will set this up this investigation as a Fair Test where you;
- identify the independent and dependent variables
- identify variables to be controlled
- suggest the CONTROL, which is the comparison trial.
- write an hypothesis,
- accurately measure,
- conduct three trials within a team,
- record data,
- compare to other teams
- plot average data on a graph
From your boiling point data you can calculate the salt concentration of sea water.
The measurements below are the salt concentrations in a unit called milliSiemens. It is a measure of electrical conductivity. (Salt solutions conduct electricity.)
Calibrate your sea concentration to the salt concentration below.
Now convert the values for salt concentrations in milliSiemens into % concentrations.
Discussion
Improvements to the Design of the Investigation
Accuracy of measurement
Validity
Improvements to the Design of the Investigation
Accuracy of measurement
- Suggest how to improve accuracy of measurements that were taken.
Validity
- Did we select solutions to test that matched the salt concentrations of the land where these plants are to be grown?