Fundamentals of Chemistry Flashcards
What is chemistry?
Chemistry is the science that examines the materials of the universe and the changes these materials undergo.
Chemistry is the scientific study of the properties and behavior of matter.
dif nuclei vs nucleus
nucleus singular
nuclei plural
what is a substance?
any matter that has a particular set of characteristics that differ from the characteristics of another kind of matter is called a substance.
For example: water carbon dioxide urea glucose common salt oxygen etc are different substances.
what is an element?
A substance that cannot be converted to other simpler substances is called an element.
Elements are the simplest chemical forms and thus can not be broken down through chemical reactions.
They are made up of only one type of atoms.
positively charged ions are called?
cations
negatively charged ions are called?
anions
if an atom loses an electron the charge will be?
positive+ cations
if an atom gains an electron the charge will be?
-ve negative anions
metal atoms _______ electrons. why?
lose
Metals are found on the left side of the periodic table, and they typically have fewer electrons in their outermost shell.
non-metal atoms ______ electrons.why?
gain
non-metals are less & they also have more valence elelctrons which means that have tendency to gain rather to lose all the electrons.
Z is the symbol for
Atomic number
Atomic number?
no. of protons
A represents?
mass number
What is molar mass?
the mass of one mole of substance
what is a compound?
A pure substance that consists of two or more elements held together in fixed proportions by natural forces called chemical bonds.
fixed proportion: in water (H2O), there are always two hydrogen (H) atoms for every one oxygen (O) atom. This is a fixed proportion. It doesn’t matter where the water comes from or how it’s produced; the ratio of two hydrogen atoms to one oxygen atom remains constant.
what is a mixture?
An impure substance that contains two or more pure substances that retain their individual characteristics.
A mixture can be broken down into two or more pure substances by physical methods.
what is 1 mole = to
6.022 x 10 raised to 23 no. of particles
what is Avogadro’s no. represented by?
NA
Physical chemistry
The branch of chemistry that deals with laws and theories to understand the structure & changes of matter. It is the study of the physical features of compounds.
Organic Chemistry
The branch of chemistry that deals with substances mainly containing carbon and hydrogen, along with other elements like oxygen, nitrogen etc.
Inorganic chemistry
deals with chemical compounds other than hydrocarbons.
It covers all the materials that are not organic or the compounds that do not contain a carbon-hydrogen bond.
Biochemistry
The branch of chemistry that deals with physical and chemical changes that occur in living organisms is called biochemistry. It is the discipline combining the study of chemistry with the study of biology, or in other words a sub-discipline of both chemistry and biology
Industrial chemistry
deals with the methods and use of technology in the large-scale production of useful substances for the benefit of humanity
Nuclear chemistry
The branch of chemistry that deals with the changes that occur in atomic nuclei.
Environmental chemistry
the branch of chemistry the deals with the chemical and toxic substances that pollute the environment and their adverse effects on human beings.
Analytical chemistry
deals with the methods and instruments for determining the composition of matter.
what is a chemical formula?
The chemical formula of a compound is a symbolic representation of its chemical composition.
The chemical formula of compounds tells us which elements are present in it and the whole number ratio of their atoms.
HCL H2SO4 NaCl
what is an empirical formula?
The empirical formula of a compound is the chemical formula that gives the simplest whole-number ratio of atoms of each element.
what is a molecular formula
A molecular formula gives the actual whole numbers ratio of atoms of each element present in a compound.
amu full form
atomic mass unit
The formula for finding no. of moles?
No. of moles= mass in gram (given)/molar mass
formula for finding mass (in grams)?
Mass in gram= No. of moles x molar mass
what are free radicals?
A free radical is an atom that has an unpaired electron, is highly reactive, and bears no electrical charge.
find mass number?
mass number is the sum of neutrons and protons
as protons=atomic number
so neutrons are left
no. of neutorns= mass no. - atomic no.
An ionic compound is represented by?
Formula unit
molecular mass is used for?
molecular compounds
formula mass is used for?
ionic compounds
An element is made from one type of atom and all the atoms present in that element have the same number of __________?
Protons
Molecular mass is expressed in?
amu
Formula mass is expressed in?
amu
what are monoatomic molecules?
A molecule that contains only one atom is called monoatomic.
helium (He)
neon (Ne)
argon (Ar)
krypton (Kr)
xenon (Xe)
radon (Rn)
oganesson (Og)
what are polyatomic molecules?
Molecules that contain two or more similar or different atoms are called polyatomic molecules.
Example
S8 P4 NH3
what is a mole?
A mole is an amount of substance that contains 6.022x10 23 particles of a substance. This experimentally determined number is known as Avogadro’s number.
what are isotopes
Isotopes are defined as atoms of the same element having the same number of protons but different
number of neutrons.
what is molecular mass?
The sum of atomic masses of all the atoms present in the molecule.
what is formula mass?
The sum of atomic masses of all the atoms in the formula unit of a substance.
what is a formula unit?
The empirical formula of an ionic or covalent compound is referred to as the formula unit.
It indicates the simplest ratio between cations and anions in an ionic compound.
molar mass is expressed in?
g/mol
molecular compounds are held together by?
covalent bonds
what are ions?
An ion is an electrically charged species formed from an atom or chemically bonded group of atoms either by the gain or loss of electrons.
the chemically bonded group of atoms (the water molecule H2O) can produce two types of ions, H+ and OH-, through the gain or loss of electrons, depending on the conditions.
mass of one carbon-12 atom =?
12 amu
1 amu?
mass of one C-12 atom / 12
