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Are these objects made of the same material? Section 1: It is possible to observe or measure physical properties without changing the identity of the material. The same does not apply for chemical properties as the measurement or observation of them changes the material’s identity. Physical properties can be categorized into two groups: extensive and intensive properties. Extensive properties are additive and dependent on the sample given, they include mass, length, and volume. As for the intensive properties, which include density, and melting and boiling point, they cannot be added. When describing matter, there are two most commonly used characteristics, volume and mass. Their relationship will give you the density of a product, more specifically density is mass divided by volume. It can be used to determine a substance’s identity and furthermore to determine if two objects are made of the same material. The goal of this investigation is to calculate the density of three different objects to determine if they are made of the same material. Two objects can look different, have a different shape or color, but as long as they have the same density it means that the objects are made of the same material. Section 2: Density is the ratio between mass and volume. Mass is measured in grams and volume in mL, so the density will be given in g/mL. Mass is the amount of matter that an object contains and it can be determined by using an electronic balance. Volume is the amount of space an object occupies. There are two ways to find an object’s volume, either by measuring its dimensions or determining its displacement in water. The three objects in this investigation are two cubes and one cylinder. To start the investigation all three objects were weighed using the electronic balance, giving the mass of each object. The first method to find the object’s volume was with help of a ruler to measure the length, width, and diameter of the cylinder or the height of the cube. That gave the dimensions of the object in cm 3. It is known that 1cm 3 = 1mL, so given that information we also know the volume of that object in mL. These measurements do not have much accuracy as the ruler used in this investigation can only give at most two decimal places, as the second decimal is a digit of uncertainty. The second method used was displacement in water. A graduated cylinder was used to measure the volume of the cylinder. When measuring the cylinder’s volume, it was placed in the graduated cylinder that already had 40mL of distilled water. The initial volume is subtracted from the final volume to determine the object’s volume. Because neither one of the cubes fit in the cylinder, a spill can was used. The spill can makes it possible to determine the volume of irregular shaped objects or objects that do not fit in a graduated cylinder. The spill can is filled up to the point where any additional volume will cause the liquid to overflow into a graduated cylinder that is placed underneath the spill can’s opening. The amount of liquid in the graduated cylinder is equal to the volume of the object placed in the spill can. By letting the liquid flow into a graduated cylinder, allows for all measurements to be taken with equal accuracy. To reduce error all measurements were performed three times and discussed by all participants. The average volume of the three trials was used to find each objects’ density.

Section 3: The argument of this investigation was whether or not the objects were made of the same material. The claim was that none of the objects were made of the same material. To support that claim we determined the density of each object and compared them to see if any of them were closely related. We came to the conclusion that none of the objects’ densities were the same, which supports the claim that none of the objects were made of the same material. The physical properties of a material, such as shape or color, are not always the determinants of whether or not two objects are made of the same material. Like previously discussed, if two objects share the same density, they are made of the same material. There was a slight difference in density calculated between the two methods of measuring the object’s volume. The density of the cylinder was more precise when using the graduated cylinder, but the ruler gave a more precise measurement of the cubes since the spill can was not as precise. The spill can may cause an error because there are multiple factors that can influence it, including the amount of liquid already in the graduated cylinder and lack of precision as the measurements were not always consistent. When using the spill can we also found that the speed of which we insert the object into the can has a say in the object´s total volume. When the object was dropped into the can without caution, instead of being slowly dropped into the can it caused it to overflow more water and therefore show a larger volume. That is one error that we came across and found that impacted the outcome. We will use the ruler’s density for the cubes because the investigation showed that the ruler was more consistent and reliable than the spill can. The ruler is accurate, the graduated cylinder is the most accurate, but the spill can is the least accurate out of these three volume determining measurements. The average densities of the three objects, using the ruler were the following: gold cube=8.36g/mL., cylinder=1.1g/mL., and white cube=0.939g/mL. The densities calculated using the graduated cylinder were the following: gold cube=8.25g/mL., cylinder=1.18g/mL., and white cube=1.22g/mL. The main difference in measuring techniques appears in the difference in accuracy between the ruler and graduated cylinder for the cylinder. The graduated cylinder provides an addition significant figure then the ruler provides. The densities of the cylinder and the white cube using water displacement were very similar. That may be because of human error when using the spill can. As the tables show there is a difference in the white cube’s densities using the ruler and using the spill can. With that being said we concluded that the ruler method was more accurate as it provides more significant digits. After going around and sharing our argument with other groups we found that not every group had the same objects and therefore the claims were not the same. One group had two objects that were made of the same material and therefore their claim included that two of the three objects were made of the same material. Their results showed the same density for two out of the three objects, which supported their claim of having two objects made of the same material. Both of the groups we compared our argument with had different outcomes, but the reason for that was that we did not have the same objects to start with.

Table 1: Mass, volume by dimension, and density using the ruler method. Mass (g)

Average volume (cm3)

Density (g/cm3)

1- Gold cube

130.405

15.6

8.36

2- Cylinder

12.385

11

1.1

3- White cube

14.635

15.6

0.938

Object

Table 2: Mass, volume by displacement, and density using the water displacement method. Object

Mass (g)

Average volume (mL)

Density (g/mL)

1- Gold cube

130.405

15.8

8.25

2- Cylinder

12.385

10.5

1.18

3- White cube

14.635

12.0

1.22...