Separation Techniques
Which separation technique is used to produce pure water from seawater?
distillation
What does the Greek word "atomos" mean?
Cannot be further divided.
How many atoms are on the periodic table?
118
Describe the movement of gas particles.
Gas particles move randomly in all directions
State 3 signs of a chemical change
change in temperature, colour
formation of a precipitate
produces light and gas
smell
Which of the following will best separate tea leaves from tea?
filtration
What is the middle part of the atom called?
nucleus
Where are metals found on the periodic table?
left side
How does solid change to liquid?
melting
Chemical change - alters the chemical composition or identity of a substance. cannot be reversed
Physical change - does not alter the chemical composition or identity of the substance, only form. reversible
Name at least 3 apparatus for evaporation.
Bunsen burner/alcohol lamp, tripod, evaporating dish, wire gauze
What charge does an electron have?
negative charge
The ______columns of the periodic table are called groups.
vertical
Which state(s) can be compresses?
gas
List 2 examples each of physical and chemical change
Answers may very
Which separation technique BEST separated iron filings and water?
filtration
Dalton named the tiny particles atoms. What Greek word does "atom" originate from?
Atomos
Diffusion is the movement of molecules from an area of _____ concentration to a ____ concentration.
high, low
What are the attraction forces between particles of solids, liquids and gases?
Solid = very strong - keep particles packed and in a fixed position
Liquid = strong, enough to keep particles close
Gas = weak
Name a chemical change important in everyday life and explain its importance.
answers may vary
List three ways we use separation techniques everyday. do not use the ones states before.
answers may vary
True or False
According to Dalton's atomic theory, atoms are indestructible and indivisible.
True
How do you calculate the number of neutrons an element has?
Mass number - Atomic number
slide and roll over each other with particles still in contact with one another.
Define precipitate
creation of a solid from a solution.
mixing together to liquids to form an insoluble substance