chem shit Flashcards
Cite five ways in which you have used chemistry in the last week.
baking, breathing, washing dishes, cutting onions makes you cry, straightening hair
Name two “not-so-obvious” careers that require at least some knowledge about chemistry. In what way is chemistry used in these careers?
baker/flavourist (manipulates the chemicals in food for taste) and hairdresser (mixing hair dyes and toners)
What is a chemical reaction? How might you tell that a chemical reaction has occurred?
Process in which atoms of one or more substances are rearranged to form
different substances – new substance is formed (colour change, change of state,
heat released, etc.
Why shouldn’t you flush old medications down the toilet?
a. Chemicals can get into the water ways and fish/aquatic species can consume these and die
What is the difference between WHMIS labels and SDSs? Why are these documents important?
WHMIS symbols inform what types of hazards are associated with a chemical;
SDS provide more detailed information about how to properly handle, store and dispose of chemicals, also contain
the physical and chemical properties of
materials, their hazards and how to treat people when an accident occurs
What is your favourite WHMIS symbol? What does it look like?
skull and crossbones = death
Describe how to properly heat a test tube.
Using test tube holders, slowly bring it back and forth in the flame (do not hold it right over top of the flame)
What three pieces of safety equipment should you wear for every experiment?
Lab coat, goggles, gloves
What are ionic compounds composed of?
METAL AND NON METAL
Distinguish between ionic and covalent bonds. Give examples of compounds that contain each of these.
Ionic bonds transfer electrons (NaI); covalent bonds share electrons (CO2)
What is a lattice structure?
Arrangement of a solid chemical where the order is a positive ion followed by a
negative ion
Distinguish between single, double and triple bonds.
Single bond shares a pair of electrons, double bond shares two pairs of electrons, triple bonds share three pairs of electrons
What is a molecule?
A particle made up of two or more atoms bonded by covalent bonds
What are the diatomic elements?
Hydrogen (H₂)
Nitrogen (N₂)
Oxygen (O₂)
Fluorine (F₂)
Chlorine (Cl₂)
Iodine (I₂)
Bromine (Br₂)
In their natural forms, these elements exist as molecules, and each molecule consists of two atoms of the same element bonded together.
In what forms are sulphur and phosphorus found in
nature?
a. O2, N2, I2, Cl2, H2, F2, Cl2
b. S8 and P4
What happens to atoms during a chemical reaction?
atoms are rearranegd
Is energy added or released when a bond is broken? Formed?
Energy is added to break of bond, energy is released when bonds are formed
What is the Law of Conservation of Mass? Who discovered it?
Antoine Lavoisier – in a chemical reaction, the total mass of the substances used is equal to the total mass of the substances produced
Distinguish between open and closed systems.
Open: a system in which things can enter and leave
Closed: a system in which things can neither enter nor leave
Distinguish between reactant and product.
Reactant: a substance that undergoes a chemical change
Product: a substance formed in a chemical change
Distinguish between words equations, skeleton equations, and balanced chemical equations.
Word equation uses words to describe what happens to reactants and products in a chemical reaction
Skeleton equation provides the chemical formulas for the reactants and products, but is unbalanced
Balanced chemical equation has the same number of atoms of each element appear on both sides of the arrow
Distinguish between a subscript and a coefficient.Distinguish between a subscript and a coefficient.
Subscript is the little number on the right hand bottom beside an element, says
how many of each of that element are found within a compound/atom
Coefficient is the large number before an atom/compound – used for balancing
equations
Distinguish between endothermic and exothermic reactions. In which do products have
more energy than the reactants? In the laboratory, how can you tell if a reaction is
endothermic or exothermic? Draw an overall energy-level diagram for an endothermic
and an exothermic reaction.
Endothermic: a chemical reaction in which there is a net absorption of energy from the surroundings; energy enters the system; products have more energy than the reactants, temperature decreases
Exothermic: a chemical reaction in which there is a net release of energy to the surroundings; energy exits the system; products have less energy than the reactants, temperature increases
What is activation energy? Illustrate activation energy on an energy diagram for an
exothermic reaction.
The minimum amount of energy needed for a reaction to occur
