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Science - Year 8 (AU) > Chemistry > Flashcards

Flashcards in Chemistry Deck (26)
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1
Q

Atom

A

The smallest particle of a chemical element that can exist. The building block of matter (which makes up everything).

2
Q

Matter

A

The substance or substances of which any physical object consists or is composed.

3
Q

Atomic Particle

A

A particle of which an atom is made of.. Either a proton, neutron or electron.

4
Q

Electron

A
  • An atomic particle with a negative charge. Has a mass of 1/1840.
  • The number of electrons in an atom is the same as the atomic number.
5
Q

Neutron

A
  • An atomic particle with a neutral charge. Has a mass of 1.
  • The number of neutrons in an atom is calculated by taking away the number of protons from the atomic mass.
6
Q

Proton

A
  • An atomic particle with a positive charge. Has a mass of 1.
  • The number of protons in an atom is the same as the atomic number.
7
Q

AMU

A

An atomic mass unit (a unit of measurement of atoms). Calculated by the mass of the protons and neutrons (electrons aren’t counted in simple calculations because it weighs 1/1840 AMU)

8
Q

Electron Shell

A

An electron shell is the outside part of an atom around the nucleus. Electrons are contained in the electron shell.

9
Q

Element

A

An element is a substance which is comprised of the same type of atom (all of the atoms have the same number of protons).

10
Q

Compound

A

A compound is a substance where two or more types of atoms (or the same type of atom) are bonded together. (In mixtures the atoms are not chemically bonded).

11
Q

Periodic Table

A
  • A table of chemical elements arranged according to the atomic number so that elements with similar structures appear in columns.
  • Elements are arranged by atomic number in increasing order from left to right, top to bottom.
12
Q

Atomic Number

A

The number of protons in the nucleus of an atom of a particular element and also determines the elements place in the periodic table.

13
Q

Atomic Mass

A

The mass of an atom of a certain element. Often calculated by adding the mass of the protons and neutrons in the atom.

14
Q

Alchemists

A

A person who transforms or creates something through a seemingly magical process. They were popular during the medieval times.

15
Q

Investigations

A

A formal inquiry or systematic study.

16
Q

Observations

A

A statement based on something one has seen, heard or noticed.

17
Q

Scientists

A

A person who is studying or has expert knowledge of one or more of the natural or physical sciences.

18
Q

Chemical Symbol

A
  • An abbreviation or short representation of a chemical element; the symbols in the periodic table.
  • Chemical symbols are unique to the element.
  • Chemical symbols are usually the first letter of the name of the element, but sometimes a second letter is added. The first letter is written in capital case while the second is written in simple case.

For example - He = Helium

  • Sometimes the chemical’s old name (usually latin name) is used. The same rules regarding to the first and second letters apply.

For example - Fe = Iron (Ferrum is the Latin name for iron)

19
Q

Anions

A

Negatively charged atoms with a full valence shell that are formed when atoms gain electrons to make a full valence shell.

20
Q

Cations

A

Positively charged atoms with a full valence shell that are formed when atoms lose electrons to make a full valence shell.

21
Q

Metals

A
  • Most metals are solid at room temperature.
  • Most metals are malleable (can be bent into shapes easily).
  • Metals are good conductors of heat and electricity.
  • Metals are shiny.
22
Q

Metalloids

A
  • Elements that are not metals but have some of the properties of metals.
  • Silicon is a good example, it is not a metals but is a good conductor of electricity, which makes it a metalloid.
23
Q

Non-Metals

A
  • Non-metals are normaly very brittle (break easily).
  • Non-metals aren’t normally shiny.
  • There are more liquid non-metals at room temperature thatn liquid metals.
  • Non-metals do no tconduct electricity well.
24
Q

Valence Electrons

A
  • Valence electrons are the electrons that orbit on the outer-most electron shell of an atom.
  • Atoms without a full valence shell are unstable, which is why they gain or lose electrons to get a full valence shell.
  • Some elements are very reactive because they are the furthest away from a full valence shell (even if they lose the electrons in the valence shell, the next shell won’t have a full set of electrons either).
  • If the valence shell has few electrons, the atom will lose the valence electrons (more efficient than gaining) and make its second outer shell its new valence shell.
  • If the valenve shell has many electrons, the atom will gain more electrons (more efficient than losing) from a nearby atom and make its valence shell have a full set of electrons.
25
Q

Electron Configuration

A
  • Electron configuration refers to the amount of electrons an atom has in each of its shells.
  • The electron configuration can be derived by looking at the number of electrons an atom has (atomic number). The first shell always has only up to 2 electrons and the other shells can have upto 8. So, for example:

A magnesium atom has 12 electrons which means it has 2 in its first shell, 8 in its second shell and 2 in its valence shell (outer-most shell). You would write it like this:

2,8,2

26
Q

Molecule

A
  • Two or more atoms (same type of different) are chemically bonded together.
  • Molecules are the smallest possible form of a compound.

SIDE NOTE: If test asks about a substance being made out of only one type of particle, it is pure.