Introduction to Chemistry
If the expected value is 2.5, and your experimental values are 2.6, 2.3 and 2.4, would you say they are precise or accurate?
Accurate. They are very close to the expected value, although they are not necessarily close to each other.
What are the three subatomic particles in an atom?
electron, neutron, proton.
Which has a longer wavelength? Red light or blue light
red light
Noble gases -- they are already stable and have a full valence shell so they don't need to gain/lose any electrons.
Why do equations need to be balanced?
Law of Conservation of Mass
What is the standard unit for temperature?
Kelvin (K)
An atom has 12 protons, 12 neutrons, and 13 electrons. What is the charge of the atom?
negative 1
Which has a higher frequency? x rays or gamma rays
Gamma rays
KCl -- What is the name of this compound?
Potassium Chloride (change the second element to -ide)
A + B --> AB is what type of reaction
Synthesis
Is H2O a compound or a mixture?
What is different about two isotopes?
the number of neutrons (proton number and electron number is the same).
When we did the flame test (using candles), why did pretty colors appear?
The electrons in the chemicals were "excited" by the heat (flame) and jumped up an energy level, and when they went back down to their ground state they gave off energy in the form of electromagnetic radiation.
Two nonmetals will form what type of bond?
Covalent bond
Single replacement reaction
You look out the window and see three blue birds sitting on a branch. List one piece of qualitative data, quantitative data, and one inference.
Qualitative: They are blue
Quantitative: There are 3 birds
Inference: They belong to the same family
True or false: The sun emits energy due to nuclear fission.
False: it is due to nuclear fusion.
What makes an atom stable?
Having a full valence shell.
Ionic bonds
Covalent bonds
Which of these are the electrons being shared and which are the electrons being transferred?
Ionic -- transferred
Covalent -- shared
A substance that reacts with oxygen and produces of lot of energy in the form of heat and light is what type of reaction?
Combustion
You make a salad that has lettuce, onions, peppers, cheese, croutons, and salad dressing. Is that salad a homogeneous mixture or a heterogenous mixture.
Heterogenous mixture (not uniformulary mixed).
Nuclear fission (can you describe this process?!)
What is the most electronegative atom on the periodic table?
Fluorine
A compound with 3 electron domains and no lone pairs is what molecular shape?
What is trigonal planar (example BF3)
When a precipitate is formed, the reaction was most likely what type?
double replacement reaction