Lab 2- Density and Chemical Reactions Flashcards
Aim
To determine density of solids and liquids, observe typical chemical reaction
Density
The mass per unit volume of a substance. A physical property.
Physical properties
Can be measured without changing the chemical identity
Pure substances
All have unique densities.
Chemical equations
Represent what transpires in a chemical reaction.
Things to know writting a reaction
What the products are
Products idnetifying
By their chemical and physical properties
Identifying substances
By the use of instruments, by reaction characteristics, or both
Test
Reactions that are characteristic of a substance
Qualitative analysis
The area of chemistry concerned with identification of substances
Increase precition
Repeat a test three or more times, a precision of human error and the equiptment
Metals and acids
React to liberate hydrogen and form the metal salt of the acid
Noble metals
Do not react with acids to produce hydrogen
Unreactive metals
Can react with nitric acid, however gases that are oxides of nitrogen rather than hydrogen are formed
Metathesis reaction names
Double replacement, exchange
Presence of carbonate ion
They react with acids to liberate carbon dioxide
Confirmatory test for CO2
Is to allow it to react with Ba(OH)2, and a white precipitate will formBaCO3
Epsom salts use
As a purgative, and solutions of this salt are used to soak tired feet
Why does H2SO4 liberate heat
In the reaction with MgSO4 and H2O, it is because of the water
What is commercial bleach
A 5% solution of sodium hypochlorite
Chlorine
A pale yellow-green gas with an irritating odor, and is toxic
Iodine
Imparts a violet colour on mineral oil
Colour from Iodide and sulphuric acid
Instantly turns dark brown, with violet fumes
