Question 1 (1 point)

Why can a solution be classified as a mixture?


Question 1 options:


Both are made up of two substances that are not chemically combined.



Both are always homogeneous.



It is made up of only one substance.



Both are made up of two substances that are chemically combined.


Question 2 (1 point)

Which choice is an element?


Question 2 options:


air (N2 mixed with O2 , and CO2 )



oxygen (O2 )



sodium chloride (NaCl)



water (H2O )


Question 3 (1 point)

Which choice is a compound?


Question 3 options:


air (N2, O2 mixed with CO2)



carbon (C)



carbon dioxide (CO2 )



oxygen (O2)


Question 4 (1 point)

Which choice is a mixture?


Question 4 options:


carbon dioxide (CO2)



oxygen (O­2)



air (N2 mixed with O­2 and CO2)



carbon (C)


Question 5 (1 point)

How is a pure substance different from a mixture?


Question 5 options:


A pure substance is heterogeneous.



Pure substances cannot be separated by physical means.



A mixture is made of one substance.



Mixtures cannot be separated by physical means.


Please help!! You get 20 points!