Chemistry intro Flashcards
The science that deals with the composition, structures, and properties of matter and how matter changes under different conditions
chemistry
Any substance that occupies space and has mass
matter
The simplest form of chemical matter and contains only one type of atom
element
How many types of elements are known to science today?
118
Of the elements, now many occur naturally on Earth?
98
What do you call an element that does not occur naturally on Earth?
synthetic element
The word used to describe a substance that contains the element carbon
organic
The basic unit of matter
atoms
Atoms have a nucleus that is surrounded by negatively charged _______
electrons
The nucleus of an atom consists of ________ and ________
protons and neutrons
The number of protons equals the number of ________
electrons
________ cannot be divided into simpler substances by ordinary chemical means
atoms
This is a chemical combination of two or more atoms in definite (fixed) proportions
molecule
This is a molecule containing two or more atoms of the same element in definite proportions
elemental molecule
This type of molecule is a chemical combination of two or more atoms of different elements in definite proportions
compound molecule
This is a change in the form or physical properties of a substance without a chemical reaction or the creation of a new substance
physical change
This is a change in the chemical composition or makeup of a substance
chemical change
This is the term for characteristics that can be determined without a chemical reaction and do not involve a chemical change in the substance
physical properties
Color, solubility, odor, density, melting point, boiling point, hardness, and glossiness are examples of…
physical properties
These are characteristics that can be determined only by a chemical reaction and involve a chemical change in the substance
chemical properties
The ability of iron to rust, wood to burn, or hair to change color through the use of hydrogen peroxide are examples of…
chemical properties
This is the term for a chemical combination of matter in definite proportions
pure substance
This is a term for a physical combination of matter in any proportion
physical mixture
When liquids are mutually soluble and can be mixed together to form solutions, they are described as…
miscible
When liquids are not capable of being mixed together to form a stable solution, they are described as…
immiscible
When two immiscible liquids are combined/shaken up together, they temporarily form…
suspensions
This is an unstable physical mixture of undissolved particles in a liquid
suspensions
This is an unstable physical mixture of two or more immiscible substances, plus an emulsifier
emulsion
This substance is miscible, has no surfactant, is stable, usually clear, has small particles
solution
This substance is slightly miscible, has no surfactant, has larger particles, is unstable, usually cloudy
suspension
This substance is immiscible, includes a surfactant, is largest in size, has limited stability through an emulsifier, usually a solid color
emulsion
Also known as an emulsifier, this will allow oil and water to mix
surfactant
The head of a surfactant molecule is ______ while the tail is _______
hydrophilic (water-loving); lipophilic (oil-loving)
Give an example of a water-in-oil emulsion
cold cream, suntan lotion, styling cream, foot balms
Give an example of an oil in water emulsion
most skincare
This type of alcohol evaporates easily
volatile alcohols
An alkaline substance used to neutralize acids or raise the pH of many hair products
alkanolamines
A colorless gas composed of hydrogen and nitrogen with a pungent odor
ammonia
A sweet, colorless, oily substance, used as a solvent and as a moisturizer
glycerin
A special type of oil used in hair conditioners, water-resistant lubricants for the skin, and nail polish dryers
silicones
A term that refers to how prolonged, repeated, or long-term exposure to certain product ingredients can cause sensitivity in some people
overexposure
