Unit 1: 1.2: Properties of Matter

Question 1

A characteristic of a substance.

Answer 1

property

Question 2

Property unrelated to possible changes in the chemical composition of a substance.

Answer 2

physical property

Question 3

A property having to do with possible changes in the composition of a substance.

Answer 3

chemical property

Question 4

A characteristic that depends on the quantity of the sample.

Answer 4

extensive property

Question 5

A characteristic, such as color, that does not depend on the quantity of material present.

Answer 5

intensive property

Question 6

Capable of being pounded into various shapes.

Answer 6

malleable

Question 7

To go into solution, thus making a homogenous mixture.

Answer 7

dissolves

Question 8

Able to be dissolved.

Answer 8

soluble

Question 9

The starting material that undergoes a change in a physical or chemical change.

Answer 9

reactant

Question 10

The substance present at the end of a chemical change; the results of the reaction.

Answer 10

product

Question 11

A process in which no change in chemical composition occurs.

Answer 11

physical changes

Question 12

A chemical reaction. The products of a chemical change are different materials than the reactants.

Answer 12

chemical changes

Question 13

If sample A weighs twice as much as sample B, is it possible to tell which sample is iron and which is powdered sugar?

Answer 13

no; the weight of a sample is an extensive property that does not reveal anything about the material’s identity

Question 14

If sample A is attracted by a magnet and sample B is a white powder, is it possible to tell which sample is iron and which is powdered sugar?

Answer 14

yes; the magnetism of sample A and the physical appearance of sample B are intensive properties that can be used to identify sample A as iron and sample B as powdered sugar

Question 15

Ethanol is a colorless, flammable liquid. If you have two 1 gallon containers labeled sample A and sample B, and each is filled with a colorless liquid, is it possible to tell which sample is water and which is ethanol just by looking at them?

Answer 15

no; the physical properties that are being compared- physical state and color- are the same for both water and ethanol, so they cannot be distinguished from one another based on this this information alone

Question 16

When liquid from sample A is splashed onto a small wood fire, the fire is extinguished. When liquid from sample B is splashed onto a small wood fire, the fire grows larger. Based on these observations, is it possible to tell which sample is water and which is ethanol?

Answer 16

yes; the chemical property that is being compared- flammability- is different for water and ethanol, so they can be distinguished based on these observations. Water is nonflammable, and sample A extinguished the fire, so sample A is water. Ethanol is flammable, and sample B caused the fire to grow, so sample B is ethanol

Question 17

A pure substance is heated in air until no further reaction takes place. A different pure substance is produced that has a mass that is 58.5% of that original substance. Can you tell whether each substance in this reaction is an element or a compound?

Answer 17

The first substance (the reactant) is a compound. When it is heated, it decomposes into a different material that is left behind and some gaseous product that escapes into the air. Because the mass of the new material is less than the mass of the original substance, the original substance must have decomposed- in which case, it cannot be an element. The new product might or might not be decomposable, so you cannot tell from the information given whether it is an element or a compound.

Question 18

After a pure substance is heated in air, a new pure substance is formed that has a mass 138% of that of the original substance. Can you tell whether each substance in these reactions is an element or a compound?

Answer 18

The second substance (the product) gained mass, so it must have combined with something in the air. The product is therefore a combination of substances and cannot be an element. You do not know if the reactant can be decomposed, so you cannot tell if it is an element or a compound.

Question 19

A sample of a shiny substance is heated in air, yielding a white powder with twice the mass. Is the change a chemical reaction? Is the powder an element?

Answer 19

A chemical reaction takes place, creating a new substance with definite properties of its own. The powder is not an element; it is a compound (a chemical combination of the shiny substance- a metal- and something else).