Oftentimes, when we deal with calculations in chemistry, we're going to run into the situation where we're dealing with extremely large numbers and extremely small numbers. Now, a convenient way to deal with this is scientific notation. Scientific notation is used to turn these small or large inconvenient numbers into manageable ones. So here we have an example of something written in scientific notation. We say it's 6.88×10-12. What's in red is called our coefficient. The coefficient is just the beginning part of the value that is equal to or greater than 1, but less than 10. Next, we have our base, which is here. This is the portion of the scientific notation value that is always 10. So that number is always going to be 10 if we're writing something in scientific notation. And then finally, the exponent, which we sometimes call the power, this is the number of places the decimal was moved to create the scientific notation value. Now we'll talk about, in a couple of videos, what happens when it's positive versus negative. What effect does that have on my value overall? Another important thing when it comes to this exponent is that it must be expressed as a whole number integer. So negative 12, positive 3, negative 2, can't be decimals or fractions, must be whole numbers. Now that we know the basic layout of scientific notation, click on the next video, and let's take a look at the example question.

# Scientific Notation - Online Tutor, Practice Problems & Exam Prep

Scientific notation is used to turn small or large inconvenient numbers into manageable ones.

## Interpreting Scientific Notation

### Scientific Notation

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### Scientific Notation Example 1

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So now that we know the major parts of scientific notation, let's put it to practice with this example question. Here it says, which of the following scientific notation values is written correctly? So if we take a look at a, here we have 1.25×10-14. If we look, the coefficient, this part here, is fine. It's a number between 1 and 10. Here our base is 10, but our error is that the exponent is not a whole number integer. It's negative one fourth. This is not written correctly. Next, if we take a look at the very beginning, we see that our coefficient here is a number that is not between 1 and 10. This is not allowed for scientific notation. The base is correct and the exponent is a whole number, but again, the coefficient is not a number between 1 and 10. So, this will not work. For c, we have our coefficient, which is a number between 1 and 10, so this is allowed. Our base is 10 and our exponent is a whole number integer, 3. So, this is a correct way of writing something within scientific notation values. So, this is our answer. If we look at d though, for d, our coefficient again is a number between 1 and 10, but our base here, our base is not 10. It's 2. Remember, if you're writing something in scientific notation, the base is always 10. The exponent is correct, but it's the base that's making it incorrect overall. So again, remember the three components of scientific notation and the limits that they each have. Following that ensures that you write scientific notation correctly every time.

### Scientific Notation

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Now that we know about scientific notation, it's going to become important on how to convert from scientific notation to standard notation. Now standard notation itself is just the normal way of writing numbers. Okay? So here, in order to go from scientific notation to standard notation, it all deals with looking at the exponent. Now we're going to say here that a positive exponent tells you to make the coefficient value larger. So if we take a look here, we have 7.17×105. Here, 5 is telling me that I need to make the coefficient larger by 5. So we're starting out with 7.17. To make it larger, I'm going to move the decimal place over to the right. So we have to move it 5 spaces. So 1, 2, 3, 4, 5. So our new way of writing this would be 717,000 as our new value.

Now what if the exponent is negative? Well, a negative exponent tells you to make the coefficient value smaller. So if we take a look here, this is negative 7. So we have 3.25. We need to make this number smaller, so we're going to have to move it to the left, and we move it over 7 spaces. So 1, 2, 3, 4, 5, 6, 7. So that's going to be 0.0000325. So, these values here would represent the normal way of writing numbers.

Now, it's inconvenient because you can see how much writing is involved in writing both of these numbers. And if our exponents were even bigger positive or, even more negative value, that'd be more movement of the decimal. That's the whole point of scientific notation. It changes these inconvenient, non-manageable numbers into something that's easier for us to read. Now that we've done this, click on the next video, and let's take a look at a practice question when we put this into practice. Remember, look at the exponent to determine if you want to make the coefficient larger or smaller.

Convert the following scientific notation values into standard notation.

a) 1.25 x 10^{-4}

b) 3.20 x 10^{-9}

c) 1.6100 x 10^{4}

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### Scientific Notation

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Now we're going to take a look at how exactly we change standard notation into scientific notation. The key is to look at the coefficient. We're going to say to convert a number into a scientific notation value, make sure the coefficient is equal to or greater than 1 but less than 10. So what we learned in the very beginning of scientific notation is the key to changing standard notation into scientific notation. So if we take a look here, we're going to say increasing the coefficient makes the exponent value decrease. Alright. So here we have a number of 0.000 145. We need to make sure that that coefficient, which we're going to make, has to fall between 1 and 10. Here is our decimal place. We're going to have to move it 1, 2, 3, 4, 5 spaces, so that we can get 1.45, which is a value between 1 and 10. Now we made the coefficient larger. Since we made the coefficient larger, that means the exponent has to become smaller. So the coefficient increased by 5, so the exponent has to decrease by 5 because they're opposites of one another.

Now, decreasing the coefficient value makes the exponent value increase. So here in this one, there is we could think of there being a decimal point there and we're going to move it over enough spaces in order to make this coefficient a number between 1 and 10. So we're going to move 1, 2, 3, 4, 5, 6, 7, 8 spaces. So that becomes 1.0132500 times 10. Now we moved over 8 spaces in order to make this smaller. So if the coefficient is decreasing by 8 spaces, that means our exponent has to be increasing by 8 spaces. So it'll be a positive 8 here. So that would be the scientific notation value for this number here. Later on, we'll talk about things such as significant figures, which will help us to even simplify this scientific notation even more because there's an awful lot of zeros here at the end. But for now, this would be the entire value that we place to show that we moved the decimal place 8 spaces over to make the coefficient smaller and thereby increasing the exponent by 8.

Now that we've seen these examples, move on to the practice question left at the bottom of the page.

Convert the following standard notation values into scientific notation.

a) 377,000

b) 0.000101

c) 707.82

#### Problem Transcript

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- Write each of the following in scientific notation with two significant figures: d. 0.000 25 cm
- Write each of the following in scientific notation with two significant figures: c. 100 000 m
- Write each of the following in scientific notation: f. 670 000
- Write each of the following in scientific notation: e. 0.0072
- Which number in each of the following pairs is larger? a. 7.2 x 10³ or 8.2 x 10²
- Which number in each of the following pairs is smaller? a. 4.9 x 10⁻³ or 5.5 x 10⁻⁹