CHEMISTRY Flashcards
Is the study of matter, its proerties, how and why substances combine or separate to form other substances, and how substances interact with energy
Chemistry
Branches of Chemistry (5)
Deals with the separation, identification and quantification of chemical substances (analytes) in a gicven sample
Analytical chemistry
Branches of Chemistry (5)
Studies the physical properties of chemical compounds using laws and concepts of physics, such as motion, energy, force, time, thermodynamics, quantum chemistry, statistical mechanics and dynamics
Physical Chemistry
Branches of Chemistry (5)
Studies the structure, composition, and chemical reactions of chemical components of living systems (plants, insects, viruses, microoragnisms, and mammals) to understand how and why chemical reaction occur in them.
Biochemistry
Measurements in Chemistry
123
Identify how many sig figs in example above
3 sig figs
Rule: All non-zero digits are significant figures
Measurements in Chemistry
12.507
Identify how many sig figs in example above
5 sig figs
Rule: Zeroes between non-zero digits are significant
Measurements in Chemistry
1.02
Identify how many sig figs in example above
3 sig figs
Rule: Zeroes between non-zero digits (decimal) are significant
Measurements in Chemistry
0.012
Identify how many sig figs in example above
2 sig figs
Rule: Zeroes to the left of the first non-zero digits are not significan
Measurements in Chemistry
2.00
Identify how many sig figs in example above
3 sig figs
Rule: Zeroes to the right os decimal point are significant
Measurements in Chemistry
0.012
Identify how many sig figs in example above
2 sig figs
Rule: Zeroes to the left of the first non-zero digits are not significan
This refers to the closeness of a measured value to a standard or known value
Accuracy
This refers to closeness of two or more measurements to each other aka repeatability
Precision
Is anything that occupies physical space and has mass and inertia
Matter
What are the 2 kinds of Matter?
Pure substance and Mixture
2 kinds of matter
Has contant composition and properties are constant throughout the sample (one set of properties)
ex. melting point, color, boiling point
Pure substance
2 kinds of matter
Combination of two or more substances that are not chemically united and do not exist in fixed proportions to each other
ex. most natural substances
Mixtures
2 kinds of matter:
2 Types of Pure Substances
Elements and Compounds
2 Types of Pure Substances
Substance made up of two or more different elemnts that are joined together in a fixed ratio
Compound
2 Types of Pure Substances: Compound
3 types of compounds
- Ionic compounds
- Covalent Compounds
- Covalent Network Substances
3 types of compounds
Are compounds composed of disscrete ions or charged species
Ionic compounds
3 types of compounds: Ionic Compound
Familiarize the properties of ionic compounds
2 Types of Pure Substances
- Solid
- High melting and boiling points
- Soluble in polar liquids like water (not in nonpolar)
- Hard
- Very reactive
3 types of compounds
Molecule formed by covalent bonds
Covalent compound
Bonds
Type of bond which atoms share one or more pairs of valence electrons
Covalent bond
3 types of compounds
Familiarize the properties of Covalent Compound
- High volatility
- Weak bonds
- Insoluble in water/polar liequids
- Low melting point
- Form a molecule
- Form between two nonmetals
3 types of compounds
Consists of a network of atoms of the same or different elemnts connected to each other by covalent bonds.
Network of these bonds extends throughout crystalline structure
One of the hardest materials on earth
Havehigh melting points and poor conductivity
Covalent Network Substances
3 types of compounds: Covalent Network Substances
Familiarize the properties of Covalent Network Substances
- High melting point
- Very hard
- Non conducting
- Insoluble in any solvent
What are the 2 major properties of matter?
- Physical properties
- Chemical properties
What are the 2 properties under physical properties?
- Intensive property
- Extensive property
2 major properties of matter
Can be observed or measured without changing the composition of matter
Physical Property
2 major properties of matter
Decribe the characteristic ability of a substance to react to form new substances
Flammability, Susceptibility to corrosion
Chemical Property
2 properties under Physical Property
A physical property that will be the same regardless of the amount of matter
Intensive Property (density, color, luster, odor, malleability, conductivity, hardness, ductility, boiling point, melting point)
2 properties under Physical Property
A physical property that will change if the amount of matter changes
Extensive property
MASS, VOLUME, WEIGHT (M V W)
MEMORIZEEEE
2 kinds of changes in matter
- Physical Change
- Chemical Change
2 kinds of changes in matter
Occurs when a substance or object changes its appearance, phase, or is used in a miaxture
Molecular strufcture does not change
Physical change
2 kinds of changes in matter: Physical Change
Types of Physical Changes
- Sublimation
- Melting
- Freezing
- Boiling/Evaporation
- Condensation
2 kinds of changes in matter: Types of Physical Change
Solid to Gas:
Liquid to Gas:
Gas to Liquid
Solid to Liquid:
Liquid to solid
Answer the appropriate types of physical changes being described
Solid to Gas: Sublimation
Liquid to Gas: Boiling or Evaporation
Gas to Liquid: Condensation
Solid to Liquid: Melting
Liquid to Solid: Freezing
2 kinds of changes in matter
Occurs when the substance’s composition is changed
When bonds are broken and new ones are formed when this change occurs
Chemical Change
2 kinds of changes in matter: Chemical change
Types of Chemical Changes
- Combination/synthesis
- Decomposition
- Substitution/siNGLE Replacement
- Double Discplacement
Types of Chemical Changes
Two or more reactants unite to form a single product
Combination or Synthesis
2Na(s) + Cl2(g) → 2NaCl(s)
Types of Chemical Changes
A single reactant is broken down into two or more products
opposite reaction of combination
Decomposition
2HgO(s) → 2Hg(l) + O2(g)
Types of Chemical Changes
A single free element replaces or is** substituted** for one of the elements in a compound
Substitution or Single Replacement
Zn(s) + 2 HCl(aq) → ZnCl2(aq) + H2(g)
Cl2 is substituted / the free element
Types of Chemical Changes
For ionic compounds, the positive ion in the 1st compound combines with the negative ions in the 2nd compound, and the negative ion in the 1st compound combines with the positive ion in the 2nd compound
BASICALLY:
1st compound (+) ion + 2nd compound (-) ion
2nd compound (-) ion + 1st compound (+)
Opposite charges
Double displacement reaction
AgNO3 + NaCl → AgCl + NaNO
Exchange of partners yuck
What are the 2 types of mixtures
- Homogenous
- HETERogeneous
2 types of mixtures
Two or more substances that form the mixture are evely distributed througout the mixture
Ex. Vinegar (ethanoic acid + water)
Homogenous mixture
bading
2 types of mixtures
Two or more substances that form the mixture are not evenly distributed throughout the mixture
Ex. water and oil
TUBIG AT LANGISSSSSSSS~~~ iykyk
Heterogenous mixtures
straight ka aw
Mixture:
Familiarize the Solubility rules
Soluble:
1. Alkali metals (Group IA)
2. Ammonium (MH4) copumds
3. Nitrates, Chlorates, Perchlorates (NO3, ClO3, ClO4)
4. Alkali metal Hydroxides; BaOH, CaOH (B, C are only slightly soluble)
5. Chlorides, Bromides, Iodides
6. Most sulfates (SO4),
7. Calcium, Silver (CaSo4, Ag2SO4)
Insoluble:
1. Most Hydroxides (except those mentioned above)
2. Carbonates, Phosphates, Sulfides
3. Barium, Mercury, Lead (BaSO4, HgSO4, PbSO4)
What are the following 3 Laws of Chemical Combination
- Law of Conservation of Mass
- Law of Definite Proportion or Composition
- Law of Multiple Proportion
3 Laws of Chemical Combination
States that matter cannot be created or destroyed in a chemical reaction
Law of Conservation of Mass
3 Laws of Chemical Combination
States that chemical compounds are formed of constant and defined ratios of elements as determined by mass
Law of Definite Proportion or Composition
3 Laws of Chemical Combination
States that when elements form compounds, the proportions of the elements in those chemical compounds can be expressed in small whole number ratios
Law of Multiple Proportion
What are the 5 Major Atomic Theories?
- John Dalton’s Atomic theory
- Thomson’s Plum Pudding Model
- Rutherford’s Nuclear Atom Model
- Bohr’s Solar System Model of the Atom
- Quantum of Wave-Mechanical Model
Identify whivh of the 5 Major Atomic Theories
→ Matter is composed of extremely small particles called atoms that participate in chemical change
→ Element consist only of one atom
→ Atoms of one element differ from atoms from other element
→ Compound consists of atoms of two or more elements combined; always present in constant/fixed ratio
→ Atoms are neither created or destroted, but is rearranged to yield different substances from those in the reactant
John Dalton’s Atomic Theory
REMINDER: JD’s theory focused on the definition/properties of an atom, element, compound
Identify whivh of the 5 Major Atomic Theories
→ Matter is composed of extremely small particles called atoms that participate in chemical change
→ Electrons are negatively-charged particles, while Atoms are neutrally-charged
→ Atom consists of a sphere of positive matter within which electrostatic forces determine positioning of the negatively charged cporpuscles (explains the neutral charge of the whole atom)
→ These negatively charged corpuscles were evely distributed in uniform sea of positive charge, like plums in pudding
Thompson’s Plum Pudding Model
REMINDER: Bits of (-) charged corpuscles are within scattered (+) charged ions;
UHM search itsura of plum pudding
Plum: (-) charged corpuscles
Pudding: (+) charged ions
Identify whivh of the 5 Major Atomic Theories
→ Was tested by bombarding a thin of sheet of gold with a-particles abd studies the trajectory of particles after interaction with gold foil
→ Most alpha particles passed straight through the foil, indicating that atoms are mostly empty space.
→ However, a small fraction of particles were deflected at large angles (the electron orbit)
→ some even bounced back toward the source (the** nucleus**/mismong gitna which is positive charged)
Rutherford’s Nuclear Atom Model (Alpha scattering Experiment)
REMINDER: Mainly stated the existence of (+) charged nucleus and orbit of (-) charged
Identify whivh of the 5 Major Atomic Theories
→ The positively charged particles and most of mass of an atom was concentrated in an extremely small volume called nucleus
→ Negatively charged electrons surround the nucleus and that these electrons surrounding nucleus revolve around it with very high speed in circular paths called orbits
Rutherford’s Nuclear Atom Model (Alpha scattering Experiment)
REMINDER: Mainly stated the existence of (+) charged nucleus and **orbit **of (-) charged
Identify whivh of the 5 Major Atomic Theories
→ Electrons only assume only certain orbits around nucleus called stationary orbits
→ Each orbit has an **energy **associated with it (Ex. orbit close to nucleus is E1)
→ Light is **emmited **when electron jumps from higher to lower orbit (nauubusan eh); absorbed when jumps from lower to higher (nadadagdagan)
→ Energy and Frequency of light emitted or absorbed is given by the difference between 2 orbit energies
Bohr’s Solar System Model of the Atom
REMINDER: Stated the positioning of electrons, energy of orbit, Light/Energy is emitted or absorbed