Density/Mixtures
How is density calculated?
Mass/Volume
Ice melting is an example of what type of change?
Physical Change
What similarities do Elements in the same column/group usually share?
Similar chemical properties
Which atomic particle has a positive charge?
Proton
What does the pH scale describe?
Acidity or basicity of a solution
Why does oil float on water?
Oil has lower density than water
Formation of gas indicates what type of change?
Chemical Change
Where are most metals found on the periodic table?
Left and Center
Which subatomic particle has the least mass?
Electron
Which pH value represents a neutral solution?
pH 7
Saltwater is what type of mixture?
Homogeneous
A student heats sugar until it turns brown and smells burnt.
What type of change has occurred?
Chemical
What property is most common in metals?
Good Conductors
If two atoms have the same number of protons, they are —
The same element
A liquid with a pH of 3 would most likely taste?
Sour
If two objects have the same volume but different masses, what can you conclude?
They have different densities
A student is dissolving salt in water.
Later the same student recovers the salt through evaporation.
What type of change has occurred?
Physical Change
Why does the Periodic Table help scientist predict how elements behave?
Organizes elements by patterns
Why are atomic models changed over time?
New evidence improves explanations
Two cleaning solutions have pH values of 10 and 12.
Which Solution is more Basic?
pH 12
A student places a metal cube into water and it sinks immediately.
Which property best explains this observation?
Density is higher than water
The statement "total mass stays the same in a closed system applies to which Law?
Law of Conservation of Mass
An element reacts easily and is shiny and bendable.
Where is it most likely found on the periodic table?
Metal region
Why can atoms not be seen directly with the naked eye?
They are too small
Why is pure water often used as a reference point on the pH scale?
It has a pH of 7