Periodic Table Families
What family is group 1 of the periodic table?
Alkali metals
What is a hypothesis?
An educated informed guess
What family is group 17 of the periodic table?
Halogens
What is an independent variable?
The variable you change that does not depend on anything
Which elements are metalloids
Boron, silicon, germanium, arsenic, antimony, tellurium, polonium
What is the difference between qualitative and quantitative observations?
Qualitative is an observation, descriptive
Quantitative uses measurements/numbers
What family is not reactive? Tell me where it is located and why it is not reactive.
Noble gases, group 18, full valence shell so they are happy
What is a controlled experiment? What is a placebo?
Controlled experiment -> only one variable is changed
Placebo -> fake treatment to compare
What is more reactive? Potassium or sodium? Why?
Potassium. It is more electropositive, and its electrons are farther from the nucleus, making it easier for them to leave.
Design a controlled experiment to test how temperature affects the dissolving speed.
Hypothesis: Increasing temperature increases dissolving rate.
Independent variable: Temperature
Dependent variable: Time to dissolve
Controlled variables: Amount of solute, volume of water
Qualitative: Clarity of solution
Quantitative: Time in seconds