Scientific Method
What is the first step of the scientific method?
gathering information using qualitative and quantitative data
What are the three parts of an atom.
electrons, protons, and neutrons
the name of the columns on the periodic table
Groups
What are two signs that a chemical reaction has occurred?
Gas, light, temp change, new substance (precipitate), change in color or odor
The numbers that we can add into equations to balance them are called...?
Coefficients
Is the following quantitative or qualitative data: the texture of a carpet
qualitative
what part of the atom is NOT included in the atomic mass?
electrons
the reason the noble gases do not react.
They are stable due to having a full outer shell. aka 8 valence electrons
Basic principle for making sure that chemical equations and number of atoms are balanced?
Law of Conservation of Matter
The numbers that are below an element that describe how many of each element there are.
subscript
What step comes after you create a hypothesis?
plan an experiment to test one variable at a time.
How do you determine how many neutrons are in an element?
subtract the atomic number from the atomic mass
this section of the periodic table contains oxygen
non-metals
Reaction in which more energy is RELEASED than absorbed.
Exothermic Reaction
Is this equation balanced? Why or why not?
Fe2O3 + Al → Fe + Al2O3
Consider the following experiment and determine which is the independent variable:
Plant A would be place inside a box, with the absence of sunlight. Plant B would be place outside the house with sufficient amount of sunlight.
After a week we observed the effect of sunlight the growth and development of the plants.
the amount of sunlight the plant gets
how do we determine how may electrons an element has?
the atomic number
the number of neutrons in Francium (Fr)
223-87 = 136
Synthesis
How many potassium, oxygen and hydrogen atoms, respectively, there are on the product side.
2 K (s) + 2 H2O (l) → 2 KOH (aq) + H2 (g)
2, 2, 4
Consider the following experiment and determine which is the dependent variable:
A company wants to see if their new drug helps clear up your nose congestion faster. They plan on giving have the people a placebo, and the other half the new drug. They will then count the amount of tissues used by each individual.
the amount of tissues used by each individual
This refers to an element that has gained or lost electrons.
An ion
what group on the periodic table contains 5 valence electrons?
group 15
Rust is a chemical compound called iron oxide. It forms very slowly as iron reacts with oxygen and water.
What are the reactants?
Iron, oxygen, water
Balance this equation?
N2 + H2 -> NH3
N2 + 3H2 -> 2NH3