States of Elements Flashcards
Memorise what state (solid, liquid, or gas) each element is found in under standard conditions (1 atm pressure and 25 °C / 298K)
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Gas
A gas is a substance that has neither a defined volume nor shape.
Gases have the weakest intermolecular (between molecules) attractions of all the four fundamental states of matter.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Gas
Noble gases include all group 18 elements, such as helium, and are called such for the fact they are all gases under standard conditions and have low reactivity.
One atmosphere pressure (1 atm) is equivalent to about 1.013 bar or 101 kPa (kiloPascals).
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Solids have the strongest intermolecular (‘between molecules’) forces of all the four fundamental states of matter (solid, liquid, gas, plasma).
Particles within solids are closely ‘packed’ and vibrate in place, rather than moving around like particles of liquids or gases.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Most metals are good conductors of electricity because of metallic bonding and delocalised electrons. These free-flowing charged particles transmit electrical energy efficiently.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Boron is a metalloid with properties intermediate between metals and nonmetals, such as being a semiconductor and forming crystalline solid structures through covalent bonding of atoms.
Solids have the strongest intermolecular (‘between molecules’) forces of all the four fundamental states of matter (solid, liquid, gas, plasma).
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Carbon has various allotropes, including diamond and graphite, each with distinct properties due to variations in the bonding patterns of carbon atoms.
For example, diamond consists of a tetrahedral arrangement of covalently bonded carbon atoms. In contrast, graphite is made up of hexagonally-arranged carbon atoms forming ‘sheets’ that are layered and held together by weaker Van der Waals forces.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Gas
In an ‘ideal gas’ (a theoretical concept used in calculations), the individual gas molecules exhibit no attractive forces toward each other. This, however, is not a practical effect observed in nature.
Nitrogen gas has two key types of bonding: intramolecular and intermolecular.
- Intramolecular bonding refers to the three covalent bonds shared between two nitrogen atoms, forming the non-polar molecule, N2.
- Intermolecular attractions are the London dispersion forces between these rapidly moving N2 molecules as they come into proximity with each other.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Gas
As intermolecular forces rely on molecules being sufficiently close, the rapidly moving and ‘spread apart’ gas molecules have the least optimal conditions for these to occur.
Oxygen gas has two key types of bonding: intramolecular and intermolecular.
- Intramolecular bonding refers to the double covalent bond shared between two oxygen atoms, forming the non-polar molecule, O2.
- Intermolecular attractions are the London dispersion forces between these rapidly moving O2 molecules as they come into proximity with each other.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Gas
Halogen gases such as fluorine have very high electronegativities.
A gas is a substance that has neither a defined volume nor shape.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Gas
Gases are less dense than liquids or solids as they have less particles per unit of volume due to their constant, random motion.
Unlike diatomic gases such as hydrogen (H2), neon exists as unbonded atoms in its gaseous form, making it monatomic instead.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Although ‘sodium’ is usually thought of as its ‘table salt’ (NaCl) form, elemental sodium is actually a soft, silvery-white solid metal.
Solids have the strongest intermolecular (‘between molecules’) forces of all the four fundamental states of matter (solid, liquid, gas, plasma).
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Because of the nature of metallic bonding and the delocalized electrons involved, most metals are good conductors of electricity. This is because delocalized electrons are free-flowing charged particles able to transmit electrical energy from one point to another.
Group 2 metals, also known as alkaline-earth metals, have a stable oxidation state of +2. This means that for each magnesium atom in a solid structure, it contributes two delocalized electrons.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Aluminium’s most common oxidation state is +3.
During metallic bonding, it can be thought of as Al3+ ions surrounded by a sea of delocalised electrons, with each atom contributing three to this ‘pool’.
Aluminium (Al) has a strong affinity for oxygen, and so will form a thin layer of aluminium oxide (Al2O3) on its outer layer, making it highly resistant to corrosion.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Solids have a fixed shape and volume, and so don’t morph like liquids to fit the container they’re in.
Silicon is a metalloid with properties intermediate between metals and nonmetals, such as being a semiconductor and forming crystalline solid structures through covalent bonding of atoms.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Phosphorus exists in various allotropes, including white, red, and black phosphorus, with different physical and chemical properties.
In the white P allotrope, it exists as individual tetra-atomic molecules. No atom has a double covalent bond with any other, meaning every phosphorus has a lone pair of electrons, making it highly reactive.
In red P, these tetra-atomic molecules form a polymeric structure, making it far less reactive.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Sulfur has five main allotropes: α-S (orthorhombic), β-S (monoclinic), S2, S3, cyclo-S8.
The rhombic allotrope of sulfur is the most stable and is described as an octahedral shape, whilst the monoclinic form of sulfur is described as ‘needle-shaped’ crystal structure.
Solids have the lowest average kinetic energy of all the four fundamental states of matter.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Gas
Gases have the highest average kinetic energy of all the four fundamental states of matter.
In its gaseous form, chlorine exists as discrete Cl2 molecules with very weak intermolecular forces occurring between them.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Gas
Gases can be compressed far more easily than liquids or solids due to the high levels of empty space between gas molecules.
Gases are less dense than liquids or solids as they have less particles per unit of volume due to their constant, random motion.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Because of the nature of metallic bonding and the delocalised electrons involved, most metals are good conductors of electricity.
This is because delocalised electrons are free-flowing charged particles able to transmit electrical energy from one point to another.
Group 1 metals, also known as alkaline-earth metals, have a stable oxidation state of +1.
This means for each potassium atom in a solid structure, it contributes one delocalised electron.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Group 2 metals, also known as alkaline-earth metals, have a stable oxidation state of +2.
This means for each calcium atom in a solid structure, it contributes two delocalised electrons.
Metals such as calcium are described as being ‘soft’.
This relates to the fact that the force required to cause layers of atoms to slide past each other is comparatively lower in these metals.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
The two major categories of solid substances are crystalline and amorphous. Some elements may have different allotropes that exist in either of these forms.
Most metals are crystalline in their solid state.
The crystalline structure of scandium is ‘hexagonal close-packed’ (hcp).
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Titanium has a high strength-to-weight ratio.
The size, mass, and arrangement of atoms in a solid determines its density.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
The crystal structure of vanadium is ‘body-centred cubic’ (bcc).
Solids have the lowest average kinetic energy of all the four fundamental states of matter.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Chromium’s crystal structure is ‘body-centred cubic’ (bcc).
Chromium (Cr) is a solid under standard conditions. It is a transition metal commonly used in the manufacturing of stainless steel.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Brittle metals such as manganese will crack more easily when they are put under stress (i.e. force is applied to them).
Solids have a fixed shape and volume, and so don’t morph like liquids to fit the container they’re in.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Depending on the temperature, iron’s crystal structure will either be ‘body-centred cubic’ (bcc) or ‘face-centred cubic’ (fcc).
Because of the nature of metallic bonding and the delocalised electrons involved, most metals are good conductors of electricity.
This is because delocalised electrons are free-flowing charged particles able to transmit electrical energy from one point to another.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Cobalt has two crystallographic structures: hexagonal close-packed (hcp) and face-centred cubic (fcc).
The presence of delocalised electrons in a metal allow for the transmission of light (electromagnetic energy) and so solids such as cobalt appear lustrous.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Nickel has one crystallographic structure: face-centred cubic (fcc).
Solids have the strongest intermolecular (‘between molecules’) forces of all the four fundamental states of matter (solid, liquid, gas, plasma).
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Copper has one crystallographic structure: face-centred cubic (fcc).
The ability of atoms to slide past one another into new configurations without breaking their metallic bonding gives rise to metals such as copper being ductile (able to be drawn into wire).
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Metals such as zinc tarnish in air.
This is the thin layer of corrosion that forms on the surface of a metal when its atoms react with surrounding oxygen.
Zinc has one crystallographic structure at room temperature: hexagonal close-packed (hcp).
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Metals such as gallium are described as being ‘soft’.
This relates to the fact that the force required to cause layers of atoms to slide past each other is comparatively lower in these metals.
Metals such as gallium are described as being ‘soft’.
This relates to the fact that the force required to cause layers of atoms to slide past each other is comparatively lower in these metals.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Germanium has two key allotropes, α-Ge and ß-Ge, which exist under different conditions to each other.
Brittle metalloids such as germanium will crack more easily when they are put under stress (i.e. force is applied to them).
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Arsenic has three key allotropes; grey, yellow, and black.
Their arrangements of atoms are layered, tetrahedral, and amorphous respectively.
Arsenic’s ‘grey’ allotropic form is its most stable at room temperature, and a good conductor of electricity.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Selenium has three key allotropes; grey, red, and black.
It’s two key physical forms are a powder and a metallic structure.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Liquid
Liquids will move to fit the container they’re in due to the fact the particles are free-flowing, but are essentially incompressible (will not change volume or density when pressure is applied).
Viscosity is a property of liquids which describes their resistance to changing shape or opposition to flow.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Gas
Gases can be compressed far more easily than liquids or solids due to the high levels of empty space between gas molecules.
It has the highest average kinetic energy of all the four fundamental states of matter.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Rubidium has one crystallographic structure: body-centred cubic (bcc).
Metals such as rubidium are described as being ‘soft’.
This relates to the fact that the force required to cause layers of atoms to slide past each other is comparatively lower in these metals.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Solid strontium has a face-centred cubic (fcc) crystal structure.
Density and the relative ‘hardness’ of a metal are two different concepts.
It is a measure of mass per volume, while hardness is a substance’s ability to resist deformation.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Yttrium, much like many other metals is described as being ‘soft’.
This means that it is malleable (able to be reshaped with little force and without cracking or shattering).
Yttrium’s most common oxidation state is +3, and so in metallic bonding, it can be thought of as Y3+ ions surrounded by a sea of delocalised electrons, with each atom contributing three to this ‘pool’.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Zirconium is described as being a ‘hard’ metal.
This means that it has a higher resistance to surface-level deformation.
Zirconium (Zr) has a strong affinity for oxygen, and so will form a thin layer of zirconium oxide (ZrO2) on its outer layer, making it highly resistant to corrosion.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Niobium (Nb) has one crystallographic structure: body-centred cubic (bcc).
Niobium (Nb) has a relatively strong affinity for oxygen, and so will form a thin layer of aluminium oxide (Nb2O5) on its outer layer, making it highly resistant to corrosion.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
The presence of delocalised electrons in a metal allow for the transmission of light (electromagnetic energy) and so solids such as molybdenum appear lustrous.
The majority of metals, like molybdenum, appear to have a ‘silvery’ color due to the fact they do not absorb many wavelengths of incident light and so most of it is reflected instead.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
(Synthetic)
Technetium has one crystallographic structure: hexagonal close-packed (hcp).
The majority of metals, like technetium, appear to have a ‘silvery’ color due to the fact they do not absorb many wavelengths of incident light and so most of it is reflected instead.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Ruthenium has one crystallographic structure: hexagonal close-packed (hcp).
The presence of delocalised electrons in a metal allow for the transmission of light (electromagnetic energy) and so solids such as ruthenium appear lustrous.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
The majority of metals, like rhodium, appear to have a ‘silvery’ color due to the fact they do not absorb many wavelengths of incident light and so most of it is reflected instead.
Rhodium is described as being a ‘hard’ metal.
This means that it has a higher resistance to surface-level deformation.
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Palladium is part of the ‘noble metals’ and so is resistant to oxidation and the effects of many corrosive substances.
Under standard conditions, palladium’s crystal structure is face-centred cubic (fcc).
Identify the state under standard conditions.
Standard conditions are defined as 25.0 °C and one atmosphere pressure.
Solid
Silver has one key crystallographic structure under standard conditions: face-centred cubic (fcc).
Silver tarnishes in air due to reaction of sulfur compounds on the surface, resulting in a black silver sulfide.