Untitled Deck Flashcards
Can you change the number of protons in an atom? Why?
Protons determine the atom’s element, so the number of protons can’t change or else the atom will change elements; the # of protons is fixed.
Define Atomic Mass Number.
The total number of protons and neutrons in an atomic nucleus.
Define Atomic Number.
It is the number of Protons that the element has, and is unique to each element.
Define Atomic Symbol.
It is a symbol unique to each element that represents the element.
Define Electron.
Negatively charged particles which have negligible mass. The number of Electrons is equal to the number of Protons in an atom.
Define Isotope.
Atoms of the same element but different mass numbers (different numbers of neutrons).
Define Metalloids.
Elements which can act as either a metal or non-metal under certain conditions.
Define Metals.
Elements that are good conductors of heat and electricity and are generally solid at room temperature. They are Ductile and Malleable.
Define Neutrons.
Particles which do not have a charge but do have mass. The number of neutrons is equal to the Atomic Mass Number - Atomic Number.
Define Non-Metals.
Elements which are generally NOT good conductors of heat and electricity. They are not Ductile or malleable, brittle, and can break easily.
Define Proton.
Positively charged particles which have mass. The number of Protons is equal to the Atomic Number.
Define Relative/Standard Atomic Mass.
The weighted arithmetic mean of the relative isotopic masses of all isotopes of that element weighted by each isotope’s abundance on Earth.
Define Valence Shell.
The outermost electron shell of the atom.
How do Bohr diagrams work? What do they represent?
Bohr Diagrams contain a central nucleus and show the electrons in their shells, alongside the shell/electron configuration below it.
How do electrons fill up their shells?
Electrons will always fill starting with the lowest energy level first.
How do you name an Isotope?
[Name of Element] - [Mass Number]
How do you name ionic compounds? Example?
The first element is the element that is most ‘left’ on the periodic table, and the second is pronounced with an -ide suffix.
Example: Sodium Chloride : NaCl
How is the Periodic Table organised?
According to the different properties of each element.
How to ‘rename’ an Ionic Bond between two Elements? E.g. Na and O.
Cross Multiplication: Put the Charge of one Ion as the subscript of the other, and repeat vice versa.
Na+ and O-2 Na20.
How to determine what isotope an atom is?
Atomic Mass # - Atomic # = Neutrons
What are Alkaline Earth Metals?
They appear shiny with a silvery-white appearance. They have 2 electrons in their valence shell.
What are Groups?
A column of elements in the periodic table. 8 numbered groups, with Noble Gases being 0.
What are Periods?
A row of chemical elements on the periodic table where all elements in a row have the same number of electron shells.
What are atoms made of, and what are they called?
Three types of subatomic particles: Electrons, Neutrons, and Protons.
What are atoms trying to do when bonding? Why?
They are trying to have a full valence shell through bonding; to be stable.
What are some of the properties that are shown on the Periodic Table?
Atomic Symbol, Atomic Number, and Atomic Mass.
What are the Alkali Metals?
The most reactive metal elements. They appear silvery and can be cut with a knife.
What are the Halogens?
Known as the most reactive non-metals. They all have 7 valence electrons in their outer shell.
What are the Noble Gases?
Known as the least reactive elements in the Periodic Table due to having a full valence shell of electrons.
What are the Rare Earth Metals?
The final group on the Periodic Table, naturally occurring, radioactive, found as solid at room temperature.
What are the Transition Metals?
Varying amount of valence electrons. Good conductors of heat and electricity.
What are the names of the Groups in the Periodic Table?
Noble Gas, Halogens, Alkali Metals, Alkaline Earth Metals, Transition Metals, Rare earth metals.
What are the three types of elements?
Metals, Non-Metals, and Metalloids.
What does the Nucleus consist of?
The Proton and Neutron.
What is the formula of the number of Electrons per shell? Who discovered this?
2n^2, where n = shell number.
Neil Bohr.
What is the pattern for electron configurations for the first 20 electrons?
2, 8, 8, 2
Where are the electrons placed in an atom?
In orbiting shells around the nucleus.
Why do electrons orbit the nucleus?
Their negative charge attracts them towards the positive charges of the protons.
Alkaline vs Base?
A base which can dissolve into water is called an alkaline solution.
Define Acid.
A molecule or other substance which releases Hydrogen Ions when dissolved in a solution.
Define Base.
A substance that releases hydroxide ions when dissolved in a solution.
Define Indicator.
Substance which changes colour when added to an acidic or alkaline solution.
Define Universal Indicator.
A chemical which changes into a wide range of colours when mixed with an acid or a base.
Give some examples of Acids.
Foods, Cleaning Products, Digestion Fluids
Give some examples of Bases.
Soaps, Cleaning Products, Foods
How does the pH Scale work? What are its ranges?
The pH scale ranges from 0 to 14. Acidic solutions have pH values below 7.
If a solution is neither acidic nor alkaline…
it is neutral!
The more H+ ions in a substance…
The more acidic the substance is.
What are the properties of Acids?
Tastes Sour, Corrosive, React strongly with metals.
What are the properties of a Base?
Tastes bitter or soapy, Strong bases can be corrosive.
What do universal indicators show?
Many different colour changes; red = strong acid, dark purple = strong base.
What does Litmus paper do?
Acid: Blue to Red, Base: Red to blue, Neutral: Nothing.
What does Litmus Indicator Solution do?
Acid = Red, Base = Blue, Neutral = Purple.
What does a step alone the pH scale in the positive direction mean?
It correlates to a decrease in the concentration of Hydrogen Ions (H+) by a factor of 10.
What does pH historically signify?
Potential/power of Hydrogen.
What is important about Hydrogen in terms of Chemistry?
Concentration of hydrogen ions within a substance determines the acidity.
What is the etymology of acid?
It comes from the Latin word acidus that means ‘sharp’ or ‘sour’.
What is the pH Scale?
A scale that measures the concentration of free Hydrogen Ions (H+) in a solution.
Where are acids found?
Foods, Cleaning Products, Digestion fluids.
Where are bases found?
Foods, Soaps, Cleaning Products.
Why does water form in neutralisation reactions?
H+ + OH- = H20
A conclusion has;
‘In conclusion..’ + Restated aim + Summarised results + Whether or not it agrees with hypothesis.
A hypothesis has:
‘It is hypothesised’ + IV + DV + ‘If, then’ + Because (Rationale) + Can be tested.
A method has:
Numbered steps, no personal pronouns, diagrams, chronological, past tense.
An aim is made of:
‘To investigate or determine’ + what we want to achieve + what we will measure.
Graphs include:
A title, axis, headings, IV, DV, units, and scales.
Materials need to have:
Bullet points and specific amounts.
What are the materials?
A list of the materials, equipment, tools, subjects, and chemicals needed to conduct the experiment.
What is a conclusion?
A statement based on experimental measurements and observations.
What is a hypothesis?
An educated guess about an experiment and its outcomes.
What is a results section?
The section where you display your data in a diagram, graph, or table.
What is an aim?
A statement that describes the purpose and reason we are conducting the experiment.
What is the Discussion section?
A section where you analyse and interpret your results.
What is the method?
An explanation of the procedures used to conduct the procedure.
Where do you put your IV and DV in graphs and tables?
Graphs: IV on the x-axis, DV on the y-axis. Table: IV on left, DV on top.
