$$\frac{2.205\ \text{lbs}}{1.000\ \text{kg}}$$

Question 1

Which of the following best defines 'matter' as discussed in the lecture notes?

Accepted Answer

Anything that has mass and occupies space.

Question 2

A student writes the mass of an electron as $$0.0000000000000000000000000009109 g. $$What is the correct way to write this in scientific notation?

Accepted Answer

$$9.109 	imes 10$$^{-28}$$ g

Question 3

Which of the following is NOT an SI base unit?

Accepted Answer

Liter (L)

Question 4

A sample has a mass of $$2.0 kg. $$Using the conversion factor $$1.000 kg$$ $$= 2.205$$ lbs, what is the mass in pounds?

Accepted Answer

$$4.4$$ lbs

Question 5

Which of the following numbers has exactly three significant figures?

Accepted Answer

1.10 $$	imes$$ $$10^4$$

Question 6

When multiplying $$2.222 (4 $$significant figures) by $$0.11 (2 $$significant figures), how many significant figures should the answer have?

Accepted Answer

2

Question 7

Which of the following is the correct decimal prefix for $$0.000001$$?

Accepted Answer

micro ($$\mu)$$

Question 8

A measurement is recorded as $$53.43689 m. $$What is the value rounded to four significant figures?

Accepted Answer

$$53.44 m$$

Question 9

Which of the following best describes a 'chemical' as defined in the lecture?

Accepted Answer

A substance that always has the same composition and properties wherever found.

Question 10

Which step in the scientific method involves forming a tentative explanation for an observation?

Accepted Answer

Hypothesis

Question 11

A student needs to convert $$123000$$ meters to kilometers using decimal prefixes. What is the correct answer?

Accepted Answer

$$123 km$$

Question 12

Which of the following is a derived SI unit?

Accepted Answer

Cubic meter ($$m^3)$$

Question 13

Which of the following numbers is written correctly in scientific notation?

Accepted Answer

$$1.2 	imes 10$$^{-6}$$ s

Question 14

A bowl contains 12 eggs. How many dozens of eggs are there?

Accepted Answer

1 dozen

Question 15

Which of the following statements about significant figures is TRUE?

Accepted Answer

Trailing zeros right of the decimal place are significant.

Question 16

A sunscreen contains titanium dioxide, vitamin E, and vitamin C. According to the lecture, is it truly 'chemical-free'?

Accepted Answer

No, because all ingredients are chemicals.

Question 17

Which of the following is the correct way to express $$0.00000012$$ seconds using the micro ($$\mu) $$prefix?

Accepted Answer

$$0.12$$ $$\mus$$

Question 18

When adding $$1.11 cm $$and $$0.222 cm$$, what is the correct answer with the proper number of significant figures?

Accepted Answer

$$1.33 cm$$

Question 19

Which of the following is the correct conversion factor to use when converting from kilograms to pounds?

Accepted Answer

$$\frac{2.205\ 	ext{lbs}}{1.000\ 	ext{kg}}$$

Question 20

Which of the following is the correct result for $$10^8$$ 	imes $$10^{-3}$$ \div $$10^{-4}$$?

Accepted Answer

$$10^9$$

Introduction to Chemistry: Matter, Measurement, and Scientific Notation

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