chapter 1
what protects your eyes when in a lab?
goggels
what is meant by physical form?
elements and compounds exit in physical form by being a gas, liquid, or solid, but there is also a aqueous, which dissolves into a clear substance.
what are Isotopes?
chemical element is an atom that has a different number of neutrons (that is, a greater or less then atomic mass) than the standard for that element. The atomic number is the number of protons in an atom's nucleus.
how does the rule of zero work?
rule of zero works because the charges have to cancel each other out.
What are molecular formulas?
a formula giving the number of atoms of each of the elements present in one molecule of a specific compound.
list 3 things you should do before beginning a lab?
1- dress appropriately, tie your hair back, roll up your sleeves and wear closed-toe-shoes.
2-be sure to read the instructions for the procedure carefully. ask your teacher if any questions.
3- before starting lab with chemicals put on safety goggles and gloves.
describe the difference between a element and a compound.
compounds and elements differ in behavior. although elements are the building materials of all matter, they are the builders for compounds, to combine specific rations.
what is the differnece between atomic number and atomic mass?
Atomic mass is the weighted average mass of an atom of an element. The mass number is a count of the total number of protons and neutrons in an atom's nucleus.
How did a can a flame test provide evidence that specific atoms are presented in compounds?
the atoms could be represented and proved if they contain specific compounds because the coloer of the flame will show.
What is the octet rule?
the octet rule strongly governs the number of atoms for each element in a molecule.
what is chemistry?
chemistry is the study of substances around you. it is the study of matter and how matter can be changed.
what 3 phases of matter can water encounter?
liquid, solid,ice, and gas in the atmosphere.
what is the relationship betweent atom and elements?
atoms have at least as many neutrons as protons. An element is a substance that is made entirely from one type of atom.
what is a polyatomic ion?
A polyatomic ion is an ion composed of two or more atoms.
Explain the Lewis dot structuer.
is a very simplified representation of the valence shell electrons in a molecule. It is used to show how the electrons are arranged around individual atoms in a molecule. Electrons are shown as "dots" or for bonding electrons as a line between the two atoms.
When you know the amount of matter in a object, it is measured in grams or kilograms. What is this called?
mass conservation.
what is the LAW OF CONSERVATION OF MASS?
the law is that matter could not be created or destroyed.
what is the average atomic mass?
The average atomic mass of an element is the sum of the masses of its isotopes, each multiplied by its natural abundance
what are valence electrons?
a single electron or one of two or more electrons in the outer shell of an atom that is responsible for the chemical properties of the atom.
define smell categories.
Humans Can Smell 10 Types of Odors.
why are most chemistry containers made out of glass?
because they are designed to measure mass and volume, and to mix, cool, heat, and observe with out shattering, they are also clear which makes it easy to observe, the container (glass) is also easy to clean and reuse.
how is a periodic table organized?
elements in a periodic table are arranged based on similarities in their chemical and physical properties.
what are the 4 nuclear reactions?
What are iconic compounds?
Ionic compounds are compounds made up of ions. These ions are atoms that gain or lose electrons, giving them a net positive or negative charge.
what is the HONC 1234 rule
A rule that states that in most molecules, H makes 1 bond, O makes 2 bonds, N makes 3 bonds, and C makes 4 bonds.