A substance that cannot be separated into simpler substances by physical or chemical means is a(n)
compound
mixture
element
period
A chemcial combination of two or more different elements is a(n)
solution
compound
element
period
Which of the following is an example of an element?
water
air
sugar
oxygen
Which of the following is an example of a compound?
gold
silver
aspirin
copper
Which of these is an example of a homogeneous mixture?
silicon
air
nickel
coins in a piggy bank
Identify the type of change taking place : breaking a pencil in half
chemical
physical
What type of change is represented by grinding coffee beans?
chemcial
physical
What type of change is represented by hard-boiling an egg?
chemcial
physical
What type of mixture is represented in stainless steel?
homogeneous
heterogeneous
What type of mixture is represented by wild bird seed?
homogeneous
heterogenous