Slides in ACS ChemCom 6e Image PPTS - Unit 1A
Look at book intro.
More practice with chemical and physical properties
Matter is anything that has mass and takes up space.
matter is anything that has mass and takes up space.
The mass of an object is a measure of the amount of matter the object contains.
Basic units of measure in the metric
mass- grams or kilograms
volume -milliliter, cubic centimeters or liters
length-cm or meters
1000 grams (g) = kilogram (kg)
1000 milliliters(mL) or cm3 = 1 liter
100 centimeters (cm) = 1 meter (m)
In chemistry, you will often encounter very large or very small numbers.
A single gram of hydrogen, for example, contains approximately 602,000,000,000,000,000,000,000 hydrogen atoms.
Try typing this number into your calculator
You can work more easily with very large or very small numbers by writing them in scientific notation.
In scientific notation, a given number is written as the product of two numbers: a coefficient and 10 raised to a power.
For example, the number 602,000,000,000,000,000,000,000 can be written in scientific notation as 6.02 x 1023.
The coefficient in this number is 6.02. The power of 10, or exponent, is 23.
975402 in scientific notation?
9.75402 x 105
not 97.5 x 10 4 or anything else
Why would we want to use scientific notation instead of standard notation?
Numbers less than one have a negative exponent when written in scientific notation. The value of the exponent equals the number of places the decimal has been moved to the right.
0.000 008 = 8 x 10–6
0.00736 = 7.36 x 10–3
When writing numbers greater than ten in scientific notation, the exponent is positive and equals the number of places that the original decimal point has been moved to the left.
6,300,000. = 6.3 x 106
94,700. = 9.47 x 104
Are these two numbers equal?
5086 5.086 x 103 why
0.000692 6.92 x 10-4 why
0.002 2 x 10 3 why
Using your calculator convert the following numbers into scientific notation
Convert the following number into standard notation.
2.65 x 10-2
3.2 x 104
6.716 x 10 -12
Using Scientific Notation
Solve each problem and express the answer in scientific notation.
a. (8.0 x 10–2) x (7.0 x 10–5)
b. (7.1 x 10–2) + (5 x 10–3)
c. (5.2 x 103) / ( 1.6 x 10-5)
4.0 x 10-3/2.0x 10-5
6.0 x 105/3.0x10-3
Qualitative data-descriptive, non-numerical.
What are some data we could observe about this____
Quantitative data or measurements- numbers with units.
What are some data we might want to measure for this ________