CHAPTER 2 - ATOMS, IONS, AND COMPOUNDS Flashcards
What is an atom comprised of?
Proton, Neutron, Electron
What is the relative masses of protons, neutrons and electrons?
P: 1
N:1
E: 0.0005 or 1/1836th of a proton
What are the charges of a proton, neutron and electron?
P: +
N: No charge
E: -
How many elements are there on the periodic table?
114 (as of 2014)
118 (as of 2018)
What is an isotope?
Atoms of the same element wit different numbers of neutrons and different masses (Same Protons and electrons)
Mass Number =….?
Number of protons+number of neutrons
Atomic number (Proton number) =…?
Number of protons
Does the varying number of neutrons in an isotope change its chemical reactivity?
No as there are the same amount of electrons and Neutrons have no effect on a reaction of an element
What is a difference that can be seen through isotopes of an element?
Higher mass of an element
Higher melting point/BP
Higher density
What does heavy water do?
Controls processes in Nuclear reactors
How is Heavy water different to normal water?
Hydrogen atoms contain a Neutron
Relative mass of 2
What is Heavy water also known as?
Deuterium (D)
What is another isotope of water and how is it different from water and deuterium?
Tritium (T) and it contains 2 neutrons per hydrogen atom (relative mass of 3)
What is the relative mass of a molecule of
H2O
D2O
T2O
18
20
22
Predict how the melting point, boiling point and density of T2O would be different from H2O and D2O
Melting point would be higher, density would be greater
What is a Cation?
A positive ion (Positive to iron a cat)
More protons than electrons
What is an Anion?
Negative ion
More electrons than protons
State the number of protons, neutrons and electrons in the following isotopes
12 6C
13 6C
14 6C
6P,6N,6E
6P,7N,6E
6P,8N,6E
Iron contains a mixture of 4 different isotopes 54 Fe, 56 Fe, 57 Fe and 58 Fe
State how these isotopes differ
State the similarity between these isotopes
Contains different number of neutrons
Nuclei contains same number of protons
State the number of protons neutrons and electrons in the following isotopes
15 7N
109 47Ag
207 82Pb
P7,8N,7N
P47, N62, E47
P82, N125, E82
State the number of protons, neutrons and election in the following ions:
41 19 K+
34 16 S2-
53 24 Cr3+
P19 N22 E18
P16 N18 E18
P24 N29 E21
State the difference in the number of protons, neutrons and electrons of the following
6Li and 7Li
18O and 18O2-
39K+ and 40Ca2+
7Li has an extra neutron
18O2- has two more electrons
40Ca2+ as one more proton
What is the mass of a Carbon-12 isotope
12u (units)
What is relative atomic mass
The weighted mean mass of an atom of an element compared to 1/12th the mass of an atom of Carbon-12
How is a mass spectrometer operated?
A sample is placed inside the spectrometer
The sample is vaporised and ionised to form positive ions
The ions are accelerated. Heavy ions move slower and are more difficult to deflect than lighter ions so the ions of each isotope are separated
The ions are detected on a mass spectrum as a mass-to-charge ratio m/z. Each ion reaching the detector adds to the signal, so the greater the abundance, the larger the signal
Define the terms
Relative isotopic mass
Relative atomic mass
Mass of an isotope relative to 1/12th of the mass of an atom of Carbon-12
The weighted mean mass of an atom of an element relative to 1/12th the mass of an atom of Carbon-12
What is a binary compound?
A compound that only contains two elements
Metal ion comes first, second element adds -ide
eg. Sodium Oxide
What is a polyatomic ion?
An ion which may contain atoms of more than 1 element bonded together
eg. Ammonium Sulfate
What is a diatomic molecule?
A molecule that exist as 2 atoms bonded together
What are the state symbols used in chemical equations
g - gas
l - liquid
s - solid
aq - aqueous (dissolved in water)
Write formulae for the following:
Potassium Oxide
Magnesium Iodide
Calcium Phosphide
Iron (III) Hydroxide
Ammonium Carbonate
Iron (II) Nitrate
K2O
MgI2
Ca3P2
Fe(OH)3
(NH4)2CO3
Fe(NO3)2
Name Each compound from the formula
AlN
(NH4)3PO4
Fe2(SO4)3
Aluminium Nitride
Ammonium Phosphate
Iron (III) Sulfate
