I also learned
the importance of significant figures and estimated digits when doing
calculations. There will always be one estimated digit in a number. All place
holder are zeros but not all zeros are place holders. All digits greater than
zero are significant.
Knowing the
difference between chemical and physical change is a very important part of
what I learned the past two weeks. Chemical
change is any change that results in the formation of new chemical substances.
Some examples include, change in color, energy, or a change in the state of
matter. In example, liquid to gas. Physical change rearranges molecules but
doesn't affect their internal structures. Something that really helped me get a better
understanding of this concept was the chemical and physical changes in matter
lab we did in class. It helped me better understand how to distinguish a
chemical from physical change.
All of the
concepts helped my lad partner and I accomplish the Metal lab efficiently. We
were given two different types of metal in two different cups. One was labeled
Cup A and the other Cup B. Our goal is to find the Density of each of the
Metals. First we calculate the mass of some of each metal and then all of each
of the metals. We calculated the mass using the electronic balance. Then we
have to calculate the volume of each of the metals. Normally we would do
length, times width, times height but in this case we will use the method of
water displacement. We fill the gradulated cylinder to the thirty milliliter
mark. And add the metal. We observe what marking the water hits now. We repeat
this step for each of the metals for both all and some. Once we have our volume
calculations we are able to calculate density. We do this by taking the mass of
the metal divided by the volume. And then we have completed the calculations
for density and are ready to graph.
