Understanding Numbers in Science

Why are numbers considered important in science?

• They are only used in chemistry.

• They are used to scare people.

• They provide an objective measure for analysis.

• They help in making subjective decisions.

What is the concentration of carbon monoxide in Earth's atmosphere?

• 0.2%

• 0.02%

• 0.0002%

• 0.00002%

How is scientific notation useful for large numbers?

• It is not used in science.

• It simplifies the representation of large numbers.

• It makes calculations more complex.

• It is only used for small numbers.

What is the scientific notation for 5 million billion?

• 5 x 10^12

• 5 x 10^15

• 5 x 10^9

• 5 x 10^18

What does a negative exponent in scientific notation indicate?

• Counting places to the left of the decimal.

• Counting places to the right of the decimal.

• A number greater than zero.

• A number less than zero.

How many water molecules are there in 18 milliliters of water?

• 6.02 x 10^23

• 6.02 x 10^22

• 6.02 x 10^21

• 6.02 x 10^20

What is the mass of a single water molecule in scientific notation?

• 2.99 x 10^-20 grams

• 2.99 x 10^-21 grams

• 2.99 x 10^-22 grams

• 2.99 x 10^-23 grams

What does the negative sign in a scientific notation exponent mean?

• The number is positive.

• The decimal point is moved to the right.

• The number is negative.

• The decimal point is moved to the left.

What is the scientific notation for 0.0171 grams of calcium?

• 1.71 x 10^-3

• 1.71 x 10^-4

• 1.71 x 10^-2

• 1.71 x 10^-1

Why is it important to include units with numbers in scientific measurements?

• Units make calculations harder.

• Units are only used in physics.

• Units provide context to the numbers.

• Units are not necessary.