CHEM (Ch. 5) Flashcards
(26 cards)
What does WHMIS stand for?
Workplace Hazardous Materials Information System
What are the steps for the scientific method?
Question, hypothesis, experiment, observations, analysis, conclusion
What is a physical property? How can you tell? + examples
A physical property is a description of a substance that does not involve forming a new substance. You can tell if it changes shape or size, it dissolves, or it changes phase (freezes, boils, condenses). examples: colour, texture, density, smell, solubility, melting point, physical state
What is a chemical property? How can you tell?
A description of what a substance does as it changes into one or more substances. You can tell if it burns, temp. changed without heating/cooling, it makes gas, changes colour or forms a precipitate
What are exothermic and endothermic reactions?
Exothermic reaction: reaction that gives off energy (feels warm on outside)
Endothermic reaction: reaction that uses up energy (feels cold on outside)
Where are protons, electrons and neutron located?
Protons and neutrons: in the nucleus
Electrons: the orbit around the nucleus
What is the Octet rule?
To become more stable, atoms will gain, lose or share valence electrons in order to obtain 8 valence electrons
Where are the noble gases located? How many electrons are in their outer valence shell (+how stable?)?
They are located to the far right of the periodic table, in group 18. There’s 8 electrons in the outer valence shell which makes them extremely stable
Where are the alkali metals located, and how stable are they?
The alkali metals are located in group 1, and are extremely reactive (bc there’s only 1 electron in the outer valence shell)
What are ionic compounds and what do they consist of?
A compound made up of one or more positive metal ions (cations) and one or more negative non-metal ions (anions)
What are molecular compounds and what do they consist of?
A pure substance formed from two or more non-metals
What is an element?
a pure substance that can’t be broken down into simpler substances
What is a period?
a row of elements on the periodic table
what is a group?
a column of elements in the periodic table with similar properties
Where are the alkaline earth metals?
second column (group 2)
Where are the halogens
in the seventeenth column, group 17
What is a Bohr-Rutherford diagram?
A model representing the arrangement of electrons in orbits around the nucleus of an atom
What is a compound?
A pure substance composed of two or more elements in a fixed ratio
What is an ion? What are cations and anions?
A charged particle that results when an atom gains or loses one or more electrons.
Cation: positive ion
Anion: negative ion
What is an ionic bond?
the simultaneous strong attraction of positive and negative ions in an ionic compound
What is an electrolyte?
A compound that separates into ions when it dissolves in water, producing a solution that conducts electricity
What is a polyatomic ion?
An ion made up of more than one atom that acts as a single particle
What is a covalent bond?
A bond that results from the sharing of outer electrons between non-metal atoms
What is a molecule?
a particle in which atoms are joined by covalent bonds
