Search results
Measuring thickness requires a tool with great precision such as calipers. However, if you know the area, mass, and density of a substance, then you could calculate the thickness. Use this formula to calculate thickness: \(\mathrm{thickness=\dfrac{volume}{area}}\) To find the volume, you would rearrange the density formula.
- The Units of Measurement
Learning Objectives. Explain the process of measurement and...
- 1.7: Measuring Mass, Length, and Volume
For example, the derived unit for area comes from the idea...
- The Units of Measurement
Learning Objectives. Explain the process of measurement and describe the three basic parts of a quantity. Describe the properties and units of length, mass, volume, density, temperature, and time. Recognize the common unit prefixes and use them to describe the magnitude of a measurement.
For example, the derived unit for area comes from the idea that area is defined as width times height. Because both width and height are lengths, they both have the fundamental unit of meter, so the unit of area is meter × meter, or meter 2 (m 2 ).
- Section 1: Chemistry and Matter
- Section 2: How Scientists Study Chemistry
- Section 3: Scientific Notation
- 103 = 1000 104 = 10000 105 = 100000
- 579, 000, 000, 000
- Coefficient Is: 5.79
- How Many Positions Are there?
- 4 = 0.0001 10-5 = 0.00001
- Coefficient Will Be 6.42
- How Many positions?
What is Chemistry?
Everything around us is made up of chemicals. From the color that makes a rose so red to the gasoline that fills our cars and the silicon chips that power our computers and cell phones…Chemistry is everywhere! Understanding how chemical molecules form and interact to create complex structures enables us to harness the power of chemistry and use it, just like a toolbox, to create many of the modern advances that we see today. This includes advances in medicine, communication, transportation, b...
Physical vs. Chemical Properties
Part of understanding matter is being able to describe it. One way chemists describe matter is to assign different kinds of properties to different categories. The properties that chemists use to describe matter fall into two general categories. Physical properties are characteristics that describes matter, such as boiling point, melting point and color. Physical Changes, such as melting a solid into a liquid, do not alter the chemical structure of that matter. Chemical properties are charact...
Elements and Compounds
Any sample of matter that has the same physical and chemical properties throughout the sample is called a substance. There are two types of substances. A substance that cannot be broken down into chemically simpler components is an element. Aluminum, which is used in soda cans, is an element. A substance that can be broken down into chemically simpler components (because it has more than one element) is a compound. Water is a compound composed of the elements hydrogen and oxygen. Today, there...
The Scientific Method
How do scientists work? Generally, they follow a process called the scientific method. The scientific method is an organized procedure for learning answers to questions. To find the answer to a question (for example, “Why do birds fly toward Earth’s equator during the cold months?”), a scientist goes through the following steps, which are also illustrated in Figure 1.7. Figure 1.7 The General Steps of the Scientific Method.The steps may not be as clear-cut in real life as described here, but...
The study of chemistry can involve numbers that are very large. It can also involve numbers that are very small. Writing out such numbers and using them in their long form is problematic, because we would spend far too much time writing zeroes, and we would probably make a lot of mistakes! There is a solution to this problem. It is called scientifi...
As you can see, the power to which 10 is raised is equal to the number of zeroes that follow the 1. This will be helpful for determining which exponent to use when we express numbers using scientific notation. Let us take a very large number:
and express it using scientific notation. First, we find the coefficient, which is a number between 1 and 10 that will be multiplied by 10 raised to some power.
This number will be multiplied by 10 that is raised to some power. Now let us figure out what power that is. We can do this by counting the number of positions that stand between the end of the original number and the new position of the decimal point in our coefficient.
We can see that there are 11 positions between our decimal and the end of the original number. This means that our coefficient, 5.79, will be multiplied by 10 raised to the 11th power. Our number expressed in scientific notation is:
The number of spaces to the right of the decimal point for our 1 is equal to the number in the exponent that is behind the negative sign. This is useful to keep in mind when we express very small numbers in scientific notation. Here is a very small number:
This number will be multiplied by 10 raised to some power, which will be negative. Let us figure out the correct power. We can figure this out by counting how many positions stand between the decimal point in our coefficient and the decimal point in our original number.
There are 5 positions between our new decimal point and the decimal point in the original number, so our coefficient will be multiplied by 10 raised to the negative 5th power. Our number written in scientific notation is:
Units and Dimensions in Physical Chemistry. Units and dimensions tend to cause untold amounts of grief to many chemists throughout the course of their degree. My hope is that by having a dedicated tutorial on them we can avoid this for Hertford chemists.
Explain the process of measurement. Identify the three basic parts of a quantity. Describe the properties and units of length, mass, volume, density, temperature, and time. Relate mass, volume, and density of a substance. Identify the prefixes, units of measurement, and unit conversions in chemistry.
People also ask
What is a measurement in chemistry?
What is a derived unit for area?
What units are used in chemistry?
How do you define a unit of volume?
How is mass measured in a laboratory?
How do you calculate volume?
Identify the three basic parts of a measured quantity; Describe the properties and units of length, mass, volume, density, temperature, and time; Convert between various metric units; Calculate density using appropriate units
