Lecture 1

Question 1

Wheat is a Mixture?

Answer 1

Combination of two or more substances where each substance retains its own chemical identity and properties. Can be separated into separate substances through physical means

Question 2

What is a Heterogeneous mixture?

Answer 2

Not uniform throughout.

i.e. Gravel, Cement

Question 3

What is a Homogeneous Mixture?

Answer 3

Uniform throughout mixture. No clumbs

i.e.

Kool-aid (stirred really well.

Question 4

What is a compound?

Answer 4

Substance composed of two ore more different elements joined by chemical bond(s)

Question 5

What is a Physical Change?

Answer 5

Changes the form or state of substance, but not composition of a substance

Question 6

What is a Chemical Change?

Answer 6

Combining, Decomposition, or combustion of substances to form new chemical bonds with different compositions.

Question 7

What is Decomposition

Answer 7

Taking a substance and splitting it into two ore more substances

i.e. H2O ———-> 2H + O

Question 8

What is chemical combination?

Answer 8

Taking two ore more substances and combining them to make one compound

i.e. Cl + H ——–> HCL

Question 9

What is a Physical Property?

Answer 9

properties that can be
measured without changing the basic identity of
the substance

Question 10

What is a Chemical property?

Answer 10

the way a substance may

change or “react” to form other substances

Question 11

How many Mg in a gram?

Answer 11

10^-6

Question 12

How many grams in a kg?

Answer 12

10^3

Question 13

How many Grams in a dg?

Answer 13

10^-1

Question 14

How many centigrams in a gram?

Answer 14

10^2

Question 15

How many mg in a gram?

Answer 15

10^3

Question 16

How many grams in a microgram?

Answer 16

10^-6

Question 17

How many nanograms in a gram?

Answer 17

10^9

Question 18

How many grams in a pg?

Answer 18

10^-12

Question 19

Does mass equal weight?

Answer 19

No, mass is a measure of the magnitude of
gravitational force experienced by and
exerted by an object

Weight is the gravitation force felt by an object while on earth.

Question 20

How would one convert Celcius to Kelvin?

Answer 20

K= 273.15+ Celcius degree

Question 21

What is an intensive Property?

Answer 21

does not depend on sample size

i.e density m/v

Question 22

What is an extensive property?

Answer 22

Dependent on sample size

i.e. mass

Question 23

What does it mean to be precise?

Answer 23

how closely
individual measurements agree with
each other

Question 24

What does it mean to be Accurate?

Answer 24

measure of how closely individual measurements agree with the correct value.

Question 25

How many significant figures?

456

Answer 25

3

Question 26

How many significant figures?

0.1004

Answer 26

4

Question 27

How many significant figures?

130.23000

Answer 27

8

Question 28

How many significant figures?

14500

Answer 28

Unknown

Question 29

How many significant figures after decimal?

3.567 / 4.23

Answer 29

3 because the number with the least significant figures will be how many significant figures your answer should have

Question 30

How many significant figures?

3.54+ 4.3567

Answer 30

two after the decimal because in addition you can only have as many decimals as the number with the least amount

Question 31

What would be a way you could mess up how many sig figs you had in the following problem?

(2.55 + 3.456) / (4.2345)

Answer 31

rounding sig figs before the final result.