C1 Atomic Structure Flashcards
What is an atom?
Atoms are very small particles made up of a electrons orbiting a nucleus.
What is an element?
A single pure substance made up of a single type of atom, found in the periodic table.
What is a compound?
Something made up from different elements, chemically bonded together.
What is a mixture?
A mixture consists of two or more different substances, not chemically joined together.
What is the nucleus made up of?
Protons and neutrons.
What orbits the nucleus?
Electrons
What is the big number called?
Mass number
What does the mass number represent?
Protons + neutrons.
What is the small number?
The atomic number.
What does the atomic number represent?
Number of protons.
What are the 3 subatomic particles?
Electrons, neutrons, protons.
What was the Greek model of the atom?
The smallest thing you could get was an atom ( small, hard sphere).
Who discovered the election?
JJ Thompson
What was the plum pudding model?
Blob of positive charge with negative charge dotted around like plums in a pudding.
Who discovered the proton?
Ernest Rutherford
What was the nuclear model?
Hard, dense nucleus in middle of the atom because only a small number of alpha particles hit it.
What was Rutherford’s scattering experiment?
Rutherford’s scattering experiment helped to explain the reflection of alpha particles. He fired alpha particles at a gold sheet.
What was the Bhor model?
The Bhor model suggested by Niels Bohr helped to explain why electrons were found in shells/ energy levels.
Who discovered the neutron?
James Chadwick
What did James Chadwick help to explain?
He helped to explain why some atoms of the same element were heavier than others.
What is abundance?
How common something is.
What is an isotope?
Atoms of the same element which have the same number of protons but a different number of neutrons.
How many electrons can the first shell hold?
2
How many electrons can the second shell hold?
8
Why do electrons orbit the nucleus?
They are held there by electrostatic attraction. The negatively charged electrons are drawn to the positive charge of the protons/nucleus.
What is the mass of an electron?
0 (very small)
What is the mass of a proton?
1
What is the mass of a neutron?
1
What is the charge of an electron?
-1
What is the charge of a proton?
+1
What is the charge of a neutron?
0
In Rutherford’s scattering experiment, how many alpha particles fired back?
1 in 8000.
What is an ion?
An atom that has lost or gained electrons.
Why do atoms try to gain/lose electrons?
So that they have a full outer shell and become more stable.
What are Group 0 known as?
Noble gases
What are Group 7 known as?
Halogens
What are Group 1 known as?
Alkali metals
What are Group 2 known as?
Alkali Earth metals
What are rows in the periodic table known as?
Periods
What are columns in the periodic table known as?
Groups
Why are Group 0 elements unreactive?
Because they are already stable.
What happens to reactivity in Group 1?
As you go down the group, the elements become more reactive.
What happens to meeting point in Group 1?
As you go down the group, melting point decreases.
What happens as the distance between the nucleus and the outer shell increases?
Larger atomic radius means more election shells+ shielding so distance gets bigger, attraction is weaker and electrons are more easily lost.
What happens as you go down Group 1?
Reactivity decreases
What physical properties do transition metals have?
Good conductors, high meeting points, high densities, hard and tough, can be hammered/bent easily into shape.
What chemical properties do transition metals have?
Less reactive than alkali metals, form coloured ions of different charges, catalysts.
What are alloys?
Metal mixed in with another atom so no layers, jumbled pattern.
What are the 5 separation techniques?
Filtration, evaporation, distillation, chromatography, fractional distillation.
What is filtration?
Separates insoluble solid from a liquid.
What is evaporation?
Separates a soluble solid from a solution.
What is distillation?
Separates liquid from a solution.
What is fractional distillation?
Separates crude oil.
What is chromatography?
Separates mixtures of coloured compounds.
Metal + oxygen→
Metal oxide
Metal + chlorine →
Metal chloride
Metal + water →
Metal hydroxide + hydrogen
Acid + metal →
Metal salt + hydrogen
Acid + alkali →
Metal salt + water
Acid + metal oxide →
Metal salt + water
How did Mendeleev organise the periodic table?
In order of increasing atomic mass.
Acid + carbonate →
Salt + water + carbon dioxide
What salt does sulfuric acid make?
Sulfate
What salt does hydrochloric acid make?
Chloride
What salt does nitric acid make?
Nitrate
Why did Mendeleev leave gaps in the periodic table?
For undiscovered elements.
What is the radius of an atom?
0.1 nm (1 × 10 -10 m)
What is the radius of a nucleus?
(1 × 10 -14 m) is less than 1 / 10 , 000 of the radius of an atom.
