Chemistry Basics
Name the 3 states of matter
Name the 3 sub-atomic particles in an atom and their locations.
Electrons, Protons, and Neutrons. Electrons are in orbitals in the electron cloud surrounding the nucleus. Protons and neutrons are in the nucleus of an atom.
A molecule of water (H₂O) is best described as:
a) An element
b) A mixture
c) A compound
d) A pure atom
A compound
Write the correct formula for Magnesium Phosphide and identify whether it has ionic, covalent, or metallic bonding.
Mg3P2 : Ionic
Classify the types of reactions for the following:
NH4OH + HBr --> H2O + NH4Br _____________________________
N2 + 3H2 --> 2NH3
_____________________________
Na2CO3 --> Na2O + CO2 _____________________________
C7H16 + 11O2 --> 7CO2 + 8H2O
1. Double displacement
2. Synthesis
3.Decmoposition
4. Combustion
Name 3 lab safety rules.
Many answers acceptable
What are isotopes?
Atoms of the same element that have the same number of protons, but different number of neutrons.
_________ mixtures have a uniform composition throughout, while __________ mixtures do not
Homogenous, Heterogenous
Metallic Bonding occurs when positively charged metal ions are held together by____________ ____________ ____________ in a giant metallic lattice arrangement. (must get all 3 words correct)
Delocalized valence electrons
Balance the following:
___H2SO4 + ___ B(OH)3 ----> __B2(SO4)3 + ___ H2O
3 H2SO4 + 2 B(OH)3 ----> B2(SO4)3 + 6 H2O
What is a Meniscus and how is it formed?
The curved surface of a liquid in a container. Caused by surface tension and adhesion of water molecules.
27Al3+ How many protons, neutrons, and electrons does this atom have. What are its atomic number and mass number?
P: 13 N: 14 E: 10 AN: 13 AM: 27
Fractional distillation separates a mixture based on differences in _________________
boiling point
Explain the difference between ionic and covalent bonds.
Ionic Bond: This is the electrostatic force of attraction between metal cations and non-metal anions, formed when metal atoms transfer their valence electrons to non-metal atoms
Covalent Bond: This is the electrostatic force of attraction between shared pair(s) of electrons and the nuclei of the bonding atoms. Non-metal atoms share electrons forming covalent bonds.
List the 3 conditions for a successful reaction:
1. The reactant particles must collide
2. Reactant particles must collide with a certain minimum energy called the activation
energy (Ea)
3. Reactant particles must collide with the correct geometric orientation
What is the process of a substance changing from a solid to a gas?
Sublimation
Si-28: 92.2%, Si-29: 4.7%, Si-30: 3.1% Based on this information, calculate the average atomic mass of Si.
28.109
Name two separation techniques that separate an insoluble solid from a liquid.
Filtration & Decanting
What is an alloy?
Name an example AND an advantage of its use.
(must get all 3 parts of the question correct)
- An alloy is a mixture of two or more elements, where at least one element is a metal
Possible examples/advantages:
-Brass: harder than copper and resistance to corrosion
-Steel: Stronger/harder than iron and is resistant to rusting
Name the 4 factors (that you learned about) which affect the rate of reaction.
- Concentration of reactant/pressure
- Surface area
-Temperature
-Catalyst
Describe changes of state using the terms: thermal energy, kinetic energy and intermolecular
forces
Teacher discretion
Write the Noble Gas configuration of Cu.
[Ar] 4s¹ 3d¹⁰
Name 3 differences between compounds and mixtures
Composition:
M: Variable composition – you can vary the amount of each substance in a mixture.
C: Definite composition – you cannot vary the amount of each element in a compound.
Joined or not:
M: The different substances are not chemically joined
together.
C: The different elements are chemically joined together.
Properties:
M:Each substance in the mixture keeps its own properties.
C:The compound has properties different from the elements it contains.
Separation:
M:Each substance is easily separated from the mixture.
C:It can only be separated into its elements using chemical reactions.
Why are ionic compounds typically soluble in water, while covalent compounds are not?
Ionic compounds dissolve in water because the polar water molecules surround and separate the ions.
The partially negative part of the water molecule attracts the cations out of the solid crystal into solution and the partially positive part of the water attracts the anions out of the crystal into solution.
Covalent compounds are typically non-polar and do not interact strongly with water molecules.
In a chemical reaction, 20 g of sodium hydrogen carbonate is produced. The reaction takes 12 minutes. Calculate the rate of the reaction. Give your answer in g s−1.
12 min x 60 sec= 720 s
20g/720s = 0.028 g/s (g s-1)