Pure Substances, Mixtures, Physical Properties, and Unit Conversions

Vocabulary flashcards covering pure substances, homogeneous and heterogeneous mixtures, physical identification tests, density, mass percentage, solubility, and metric conversion tables.

Pure substance (Corps pur)

A substance in solid, liquid, or gaseous form that consists of only one single chemical species, such as water ($\text{H}_2\text{O}$) or sodium chloride ($\text{NaCl}_{(s)}$).

Homogeneous mixture (Mélange homogène)

A mixture whose individual constituents cannot be distinguished with the naked eye, such as a solution of water and mint syrup.

Heterogeneous mixture (Mélange hétérogène)

A mixture composed of at least two phases in which at least two of its constituents can be distinguished with the naked eye, such as a mixture of water, oil, alcohol, and syrup.

Physical properties (Propriétés physiques)

Characteristic properties unique to a chemical species that constitute its identity card and allow it to be identified and named, including solubility, density, and melting temperature.

Melting temperature ($T_{\text{fusion}}$)

The temperature at which a substance transitions from solid to liquid and where both states coexist; pressure has very little influence on its value, and it serves to verify purity.

Kofler bench (Banc Kofler)

A heated plate displaying a temperature gradient (such as $50\,^\circ\text{C}$ to $250\,^\circ\text{C}$) equipped with a mobile cursor index to measure the melting temperature of a substance.

Water identification test

A test using anhydrous copper sulfate powder, which turns from white to blue in the positive presence of water ($\text{H}_2\text{O}$).

Dihydrogen identification test

A chemical test in which exposing dihydrogen ($\text{H}_2$) to a lit match produces a distinctive small detonation or popping sound.

Dioxygen identification test

A chemical test in which exposing dioxygen ($\text{O}_2$) to an incandescent glowing splint causes the match to reignite.

Carbon dioxide identification test

A chemical test where exposing carbon dioxide ($\text{CO}_2$) to limewater causes the solution to turn cloudy or turbid.

Density (Masse volumique, $\rho$)

The ratio of an object's mass to its volume, expressed by the formula $\rho = \frac{m}{V}$; for air at $15\,^\circ\text{C}$, $\rho_{\text{air}} = 1{,}225\,\text{kg}\cdot\text{m}^{-3}$.

Mass percentage (Pourcentage / titre en masse, $P$)

The percentage ratio of the mass of a dissolved substance to the total mass of the solution, expressed as $P = \frac{m_{\text{solute}}}{m_{\text{solution}}} \times 100$.

Liter to cubic meter conversion

The relationship defined by $1\,\text{L} = 1\,\text{dm}^3 = 1 \times 10^{-3}\,\text{m}^3$ (or $0{,}001\,\text{m}^3$), where converting liters to cubic meters requires dividing by $1000$.

Solubility ($s$)

The maximum mass of solute that can be dissolved per unit volume of solution or solvent, given by the formula $s = \frac{m_{\text{max}}}{V}$ in units of $\text{g}\cdot\text{L}^{-1}$.

Metric mass units (Unités de masses)

Measurement units centered on the gram ($\text{g}$), with larger multiples including kilogram ($\text{kg}$), quintal ($\text{q}$), and tonne ($\text{t}$), and submultiples including decigram ($\text{dg}$), centigram ($\text{cg}$), and milligram ($\text{mg}$).

Land surface units (Unités agraires de surface)

Area units derived from the metric square system where $1\,\text{ha} = 1\,\text{hm}^2$, $1\,\text{a} = 1\,\text{dam}^2$, and $1\,\text{ca} = 1\,\text{m}^2$.