What is Science?
What is the goal of scientific methods?
To solve a problem or to better understand an observed event
Why does every sample of a given substance have the same properties?
A pure substance has a fixed composition.
Solid, Liquid, Gas
One of the first people to state that matter is made up of atoms was
A. Democritus B. Aristotle
C. Dalton D. Rutherford
Democritus
Mendeleev arranged the elements in his periodic table in order of what?
mass
What is the equation for density?
Density= mass/ volume
Examples of physical properties ( there is 6)
Viscosity, conductivity, malleability, hardness, melting and boiling points, density
The energy an object has due to its motion.
Kinetic Energy
Almost all the mass of an atom is located in its?
nucleus
An element that is shiny and conducts electric current is likely to be a
metal
Scientists use a set of measuring units called what?
SI or the International System of Units
List three common types of evidence for a chemical change?
A change in color, production of gas, formation of a precipitate.
What three factors effect gas pressure?
Temperature, volume, number of particles.
All atoms of an element have the same
atomic number
What is the symbol for gold?
Au
What is accuracy? What is Precision?
Accuracy is the closeness of a measurement to the actual value of what is being measured. Precision is a gauge of how exact a measurement is.
A pan of butter melts and then burns in a hot frying pan. Which of these changes are physical and which is chemical
Melting is a physical change. Burning is a chemical change.
Name six common phase changes?
Melting, freezing, vaporization, condensation, sublimation, and deposition.
What part of Daltons theory was modified after the discovery of isotopes?
All atoms of an element are identical
How many periods does the periodic table have?
seven
Name the four types of ways you can organize data? (graphs and tables)
Data Tables, Line graphs, bar graphs, circle graphs
Explain why sharpening a pencil is an example of a physical change
The shape and size of the pencil change but the composition does not change.
What is the difference between evaporation and boiling?
Evaporation takes place at the surface of a liquid and occurs at temps below the boiling point.
If an atom has an atomic number of 6 and a mass of 14 how many protons, electrons and neutrons are in the atom?
Six protons, 6 electrons and eight neutrons.
What element exists in almost ever compound in your body?
Carbon