Which one of the fo llowing is often easily separated into its components by simple techniques such l) as filtering or decanting?
A) homogeneous mixture
B) solutions
0 heterogeneous mixture
D) elements
E) compounds
2) An clement cannot 2)
A) be part of a heterogeneous mixture
Ji,) be a pure substance is corrccl for ___ _ 19)
A) elements B) homogeneous mixtures
Ohcterogeneous mixtures D) compounds
20) Which of the fo llowing is an example of a lieterogeneous mixture?
@ oil and vinegar B) 70% ethanol solution
20)
C) air D) sugar water
3
21) According to the Thomson model, what is the relative charge on an electron? 21)
~+2 w-1
C) +1
D) -2
E) none of the above
22) A pure substance has been isolated in the laboratory. Based on the two characteristics below, how 22) …show more content…
I. The species can not be separated by physical means.
II. The species can be separated by chemical means.
@a compound B) a heterogeneous mixture
C) an clement D) a homogeneous mixture
23) Which of the following statements is correcl? 23)
A) Elements, but not compounds, are pure substances.
B) Neither elements nor compounds are pure substances. g Compounds, but not elements, are pure substances.
@)Both elements and compounds are pure substances.
24) A sample of wood with a mass of 3.0 grams was burned in an open dish. The ashes weighed 1.2 24) grams. What happened to the rest of the wood?
@ The remaining 1.8 grams was converted into gaseous compounds.
B) The rel\laining 1.8 grams was converted into heat.
C) The remaining mass was destroyed.
D) Nothing, the burned wood simply has a mass of 1.2 grams.
E) none of the above
25) A fictional element has two naturally occurring isotopes with the natural abundances shown here: 25)
ISOTOPE ABUNDANCE
18
A) homogeneous mixture
B) solutions
0 heterogeneous mixture
D) elements
E) compounds
2) An clement cannot 2)
A) be part of a heterogeneous mixture
Ji,) be a pure substance is corrccl for ___ _ 19)
A) elements B) homogeneous mixtures
Ohcterogeneous mixtures D) compounds
20) Which of the fo llowing is an example of a lieterogeneous mixture?
@ oil and vinegar B) 70% ethanol solution
20)
C) air D) sugar water
3
21) According to the Thomson model, what is the relative charge on an electron? 21)
~+2 w-1
C) +1
D) -2
E) none of the above
22) A pure substance has been isolated in the laboratory. Based on the two characteristics below, how 22) …show more content…
I. The species can not be separated by physical means.
II. The species can be separated by chemical means.
@a compound B) a heterogeneous mixture
C) an clement D) a homogeneous mixture
23) Which of the following statements is correcl? 23)
A) Elements, but not compounds, are pure substances.
B) Neither elements nor compounds are pure substances. g Compounds, but not elements, are pure substances.
@)Both elements and compounds are pure substances.
24) A sample of wood with a mass of 3.0 grams was burned in an open dish. The ashes weighed 1.2 24) grams. What happened to the rest of the wood?
@ The remaining 1.8 grams was converted into gaseous compounds.
B) The rel\laining 1.8 grams was converted into heat.
C) The remaining mass was destroyed.
D) Nothing, the burned wood simply has a mass of 1.2 grams.
E) none of the above
25) A fictional element has two naturally occurring isotopes with the natural abundances shown here: 25)
ISOTOPE ABUNDANCE
18