Chemistry
ACT Science / Chemistry
50 Words
25m
a large molecule composed of repeating structural units, or monomers, covalently bonded together in a chain-like structure
Polyethylene is a common polymer used in the production of plastic bags, bottles, and various packaging materials.
View Full Definitioneach of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei, leading to variation in atomic mass
Carbon-12 and carbon-14 are isotopes of carbon, with the former having 6 neutrons and the latter having 8 neutrons.
View Full Definitionacting in response to a situation rather than initiating or controlling it
The company remained reactive instead of taking a proactive approach.
View Full Definitioncontaining or relating to a dangerous form of energy produced by nuclear reactions
Radioactive isotopes are used in medical imaging for diagnostic purposes.
View Full Definitiona chemical bond where atoms share electrons to form a stable molecule
Covalent bonds are like atoms sharing electron hugs to stick together.
View Full Definitiona type of chemical bond between two atoms involving the sharing of two pairs of electrons, resulting in a stronger and more stable connection than a single bond
Ethylene (C₂H₄) contains a double bond between two carbon atoms, allowing it to participate in polymerization reactions.
View Full Definitiondefining substances or surfaces that have a strong attraction to water molecules, allowing them to easily absorb or interact with water
The hydrophilic nature of cellulose fibers in paper towels makes them effective at absorbing spills.
View Full Definitioncharacterized by substances or surfaces that repel water molecules, showing little or no affinity for water
The hydrophobic coating on a rain jacket causes water to bead and roll off its surface.
View Full Definitiona chemical reaction that releases heat energy to its surroundings, typically resulting in a temperature increase
Combustion of propane in a gas stove is an exothermic reaction that releases heat and light.
View Full Definitiona chemical process that absorbs heat energy from its surroundings, often resulting in a temperature decrease
When ammonium nitrate dissolves in water, the endothermic reaction causes the solution to cool.
View Full Definitionthe weighted average mass of an atom of an element, taking into account the masses of all its naturally occurring isotopes
The atomic mass of carbon is approximately 12.01 because it averages the masses of carbon-12 and carbon-13 isotopes.
View Full Definitionthe total mass of all the atoms in a single molecule of a substance
View Full Definitionthe total number of protons and neutrons in the nucleus of an atom
The mass number of carbon-12 is 12, as it has 6 protons and 6 neutrons.
View Full Definitiona small mammal with velvety fur, tiny eyes and a long muzzle that lives underground and eats insects
View Full Definitiona container usually made of glass or plastic used in chemistry and laboratory
View Full Definitiona laboratory tool used to measure and transfer small volumes of liquid
She carefully calibrated the pipette before transferring the sample into the test tube.
View Full Definitionto rotate a substance at high speed in order to separate its components based on density, typically isolating solids from liquids
The lab technician centrifuged the blood sample to extract plasma.
View Full Definitiona special paper treated with chemicals that change color in response to certain conditions, used to test for the presence of specific substances or measure pH levels
View Full Definitiona tabular arrangement of chemical elements organized based on their atomic number, electron configuration, and recurring chemical properties
The periodic table, devised by Dmitri Mendeleev, categorizes elements into rows and columns based on their properties.
View Full Definitionto make a substance one with a liquid
The pharmacist instructed him to dissolve the medication in water before taking it.
View Full Definitionthe process of dispersing or dissolving a substance into a solvent to form a homogeneous solution
View Full Definitionthe arrangement, composition, and characteristics of a material at a microscopic level
View Full Definitiondenoting substances with a highly organized molecular structure, akin to crystals
The crystalline structure of snowflakes makes each one unique.
View Full Definitiona device used to analyze the chemical composition of small samples at a microscopic scale
View Full Definitiona substance capable of absorbing and retaining a large amount of liquid relative to its own mass
View Full Definitiona type of metallic material composed of three or more elements mixed together in varying proportions
View Full Definitiona tiny, tube-shaped structure made of carbon atoms, with remarkable strength and electrical properties
Researchers are exploring the use of carbon nanotubes in the development of stronger, lighter materials.
View Full Definitionheated to a liquid state due to high temperatures
The molten lava flowed down the mountainside during the volcanic eruption.
View Full Definitionsupporting total and extreme social or political changes
The radical activist advocated for the overthrow of the government to establish a new social order.
View Full Definitiona distinct period or stage in a sequence of events or development
The project is currently in its planning phase.
View Full Definitionthe process where calcium or calcium salts accumulate in a tissue, making it hard and rigid
The calcification of bones is essential for maintaining their strength and structure.
View Full Definitionthe process by which microorganisms convert carbohydrates into alcohol, acids, or gases
The fermentation of dough by yeast produces carbon dioxide gas, causing the dough to rise and become light and airy when baked.
View Full Definitionto eliminate or neutralize harmful substances
Environmental initiatives aim to detoxify polluted water sources for the well-being of aquatic ecosystems.
View Full Definitiona careful examination or assessment, often used in literary, philosophical, or strategic contexts
His essay was an assay of modern political anxieties.
View Full Definitiona scientist who studies the structure and properties of crystals
The crystallographer used X-ray diffraction to analyze the mineral samples.
View Full Definitiona scientist who studies the chemical composition and processes of celestial bodies to understand the formation and evolution of the universe
View Full Definitiona laboratory technique used to separate and analyze mixtures of substances based on their differential affinities for a stationary phase and a mobile phase
The scientist used chromatography to separate the pigments in a leaf extract.
View Full Definitiona type of radioactive decay where a nucleus emits a beta particle (electron or positron) to transform a neutron into a proton or vice versa
Carbon-14 undergoes beta decay to nitrogen-14 with the emission of an electron.
View Full Definitionnot having an electrical charge
Water molecules are uncharged, consisting of neutral oxygen and hydrogen atoms.
View Full Definitiona laboratory method used to determine the concentration of a substance in a solution by gradually adding a reagent of known concentration until a reaction is completed
In the chemistry lab, we used titration to find the concentration of acetic acid in vinegar.
View Full Definitiona balanced state between opposing influences or powers
The tightrope walker maintained perfect equilibrium as they carefully balanced along the narrow line.
View Full Definitionan electrical device characterized by its capacity to store an electric charge
View Full Definitiona scientist or engineer who specializes in the study and production of metals and alloys, including their properties, processing methods, and applications
The metallurgist conducted experiments to determine the optimal alloy composition for the new aerospace material.
View Full Definitionthe process by which molecules of a substance adhere to the surface of a solid or liquid, forming a thin film or layer
Activated charcoal is known for its high adsorption capacity, making it effective in purifying water and air.
View Full Definitiona renewable, alternative fuel made from organic materials such as vegetable oils, animal fats, or recycled cooking grease
The truck runs on biodiesel, which is better for the environment than regular diesel.
View Full Definitiona method of permanent hair removal that uses electric currents to destroy hair follicles
She decided to undergo electrolysis to achieve long-lasting hair removal and enjoy smooth skin.
View Full Definitionto temporarily put on hold a process or habit
The company decided to suspend production temporarily due to a supply chain issue.
View Full Definitiona specific composition of a mixture of substances, typically metals or alloys, where the melting point is at its lowest possible temperature under atmospheric pressure
The eutectic composition of the alloy ensures it melts uniformly at a precise temperature suitable for casting.
View Full Definitionto make a solution or mixture weaker or less concentrated by adding more liquid
To make it more palatable, you can dilute the juice with water.
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