C1 - Atomic Structure And Ways To Separate Mixtures Flashcards
What are atoms?
Atoms are the smallest part of an element that can exist.
What is the approximate radius of an atom?
About 0.1 nm (1x10-10 m).
How are atoms of each element represented?
By a chemical symbol, e.g., O for oxygen and Ca for calcium.
What is an element?
A substance made up of only one type of atom.
What defines a compound?
Compounds contain two or more elements chemically combined in fixed proportions.
What does the formula CO2 represent?
Carbon dioxide, with 1 carbon atom and 2 oxygen atoms.
How can compounds be separated into elements?
Only by chemical reactions.
What is the order for naming compounds of two elements?
- The name of the metal goes first
- The name of the non-metal goes second
- The non-metal name ends in -ide.
Write the word equation for the reaction of calcium and bromine.
calcium + bromine → calcium bromide.
What is the symbol equation for the reaction of calcium and bromine?
Ca + Br2 → CaBr2.
What is chromatography used for?
For separating a mixture of substances dissolved in a solvent.
What must be true about the pencil line in chromatography?
It must be above the solvent.
What is filtration used for?
For separating insoluble solids from a liquid or solution.
What is the function of filter paper?
It has tiny holes (pores) that allow small solute molecules and dissolved substances to pass through.
What is crystallization used for?
For forming crystals from a solution.
What is the gentler method for evaporating water from a solution?
Evaporating on a water bath.
What is distillation used for?
For separating a mixture of liquids.
What happens to the liquid with the lowest boiling point during distillation?
It boils and its vapour is collected as pure liquid.
What is the structure of an atom?
Atoms consist of a nucleus containing protons and neutrons, with electrons arranged in shells.
What is the charge of protons and electrons?
- Protons: +1
- Electrons: -1.
What is the maximum number of electrons in the first shell?
2 electrons.
How many electrons can the second and third shells hold?
8 electrons each.
What are ions?
Charged atoms that result from losing or gaining electrons.
What is mass number?
The number of protons plus neutrons in the atom.
What is the atomic number?
The number of protons in the atom.
What are isotopes?
Atoms of the same element with different numbers of neutrons.
Fill in the blank: Atoms have ______ overall charge.
no
What defines an atom’s electron structure?
The arrangement of electrons around the nucleus in shells.
What does the electron structure 2,6 represent?
Oxygen atoms, with 2 electrons in the first shell and 6 in the second.
