Elements, Compounds, and Mixtures
What is the definition of an element
Only 1 type of atom
Which phase changes involves the greatest increase in kinetic energy?
boiling
condensing
melting
boiling
What separation technique would be used to separate the pigments of ink
chromatography
Is boiling H2O a physical or chemical change
physical
In order to be classified as matter, something must have _________________ and ________________
mass and volume
What types of matter exist as pure substances
Elements and compounds
What phase of matter takes the shape and volume of its container?
gas
Are chemical or physical properties used to separate the components of a mixture
Physical
Intensive
True or false: whenever bonds are broken or formed, a chemical change is taking place
True
Draw and label one molecule of an element, and one molecule of a compound
Molecule of an element must be 2+ atoms bonded together that are the same type, molecule of a compound must be 2+ atoms bonded together that are different
What is one separation technique that would not work to separate a homogenous mixture
filtration, or decantation
What technique would be used to separate a homogeneous mixture of two liquids with different boiling points
Distillation
What type of change occurs when you place a beaker of water on a preheated hot plate, and gaseous water forms
Physical change
Which state of matter is the most compressible
What is the definition of a mixture
Different types of matter physically combined
Substance Boiling Point (°C)
R 45
Sq 195
T 320
Based on the data for boiling point, which would be the substance expected to make up the first fraction collected during distillation?
R; the lowest boiling point comes out first
If rice, salt, and water were all mixed together, how would you separate them out
1) Pour salt water through filter - anything dissolved will pass through filter with water, now rice is separate
2) Evaporate off the water so that salt and water are separate
If I mix two clear solutions and they form a white solid in the mixture, what type of change has taken place?
Chemical (creating two solids from a liquid is forming a percipitate)
What does temperature measure?
The average kinetic energy the the atoms/molecules in a sample
Draw a mixture of an element and a compound with at least five particles
Element = only 1 type of atom
Compound = 2+ atoms chemically bonded
The different particles should be mixed together in drawing
Draw 2 molecules of Sq2T decomposing/ chemically changing into T2 and Sq2.
Drawing should include:
2 molecules of Sq2T
1 molecule of T2
2 molecules of Sq2
Filteration
What type of change does dissolving represent?
Physical change
A student is tasked with separating a mixture of ethanol (boiling point 78) and water (boiling point 100) using distillation. What order will the components distill out of the mixture in?
Ethanol first (lower boiling point)
Water second (higher boiling point)