Chapter 4 - Elements, Compounds and Mixtures

Question 1

what is an atom?

Answer 1

smallest particle of an element

Question 2

where are metals and non-metals found in the periodic table?

Answer 2

metals found on the left of the staircase while non metals are on the right side of the staircase. most elements are metals

Question 3

properties of metals

Answer 3

1. high mp and bp
2. good conductors of electricity
3. good conductors of heat
4. strong and hard
5. malleable and ductile
6. high density
7. shiny in appearance
8. sonorous (makes a ringing sound when struck)

Question 4

properties of non-metals

Answer 4

1. low mp and bp
2. do not conduct electricity
3. poor conductors of heat
4. weak and soft
5. brittle
6. low density
7. dull in appearance
8. non-sonorous

Question 5

what is a compound?

Answer 5

pure substance containing 2 or more elements chemically combines in a ratio (H20, NaCl, CO2)

Question 6

properties of compounds

Answer 6

• fixed proportion
• can be broken down into simpler substances
• has very different properties from the elements that form it
• fixed mp and bp
• can ONLY be separated by chemical methods
• chemical rxn takes place whn compound is formed

Question 7

what is a molecule?

Answer 7

substance made up of 2 or more atoms chemically combined together.

Question 8

what are 2 ways to decompose compounds?

Answer 8

thermal decomposition and electrolysis

Question 9

what is a mixture?

Answer 9

2 or more substances NOT chemically combined

Question 10

properties of mixtures

Answer 10

• no fixed composition
• melts and boils over a range of temperatures
• same properties of the elements and/or compounds it is made up of
• can be separated by physical means
• NO chemical rxn takes place whn formed