Exam 1 review

Unit conversions

100

Convert 134 pm to cm

1.34 x 10-8

200

Convert 150 kg to g

150000 g

300

The diameter of a pupil is 0.0022 m. What is the diameter in mm

2.2 mm

400

Is the following true of false

1 mL = 1 x 10-7 L

False

500

Solve the following:

(12.63 mL –1.41 mL) x 0.845 mg/mL

9.4809

Significant figures

100

List the rules of significant figures when adding/subtracting and multiplying/dividing

Multiplication & division: Round your answer to the same number of significant figures as the number with the least sig figs 

Addition & subtraction: Round your answer to the least number of digits trailing the decimal point

200

How many significant figures are in 0.00395672

6

300

Calculate and round to the nearest sig fig

335.88 + 40.178

376.058 = 376.1

400

Determine the correct number of significant figures:

4500 

0.00204

20000.  

2

3

5

500

Calculate and round to the correct number of significant figures

7.77 x 5.3

41.181 = 41.

Atomic structure

100

Describe an isotope and give an example

An atom that has a different number of neutrons than the neutral atom

200

Describe an ion and give an example

A charged atom, the number of electrons changes from the neutral atom.

300

What do each of the numbers represent

⁷₃Li

7= Mass number

3= Atomic number

400

What is the atomic number of nickel (Ni)

28

500

An element has 20 protons, 20 neutrons, and 18 electrons. What is the name of this element

Ca²⁺

Atomic weights

100

What is the formula you use to calculate average atomic weight

Average atomic weight =(mass1xF1)+(mass 2xF2)

200

Solve for F₁ and F₂

Copper (Cu) 

Isotope 1= 63.00 amu Isotope 2= 65.00 amu

Average atomic weight = 63.55 amu

F₁= 0.725 F₂= 0.275

300

Solve for F₁ and F₂

Gallium (Ga)

Isotope 1 = 69.00 amu Isotope 2= 71.00 amu

Average atomic weight= 69.72 amu

F₁= 0.640

F₂= 0.360

400

Solve for F₁ and F₂

Rubidium (Rb)

Isotope 1= 85.00 amu Isotope 2= 87.00 amu

Average atomic weight= 85.47 amu

F₁= 0.765

F₂= 0.235

500

Solve for F₁ and F₂

Silver (Ag)

Isotope 1= 107.00 amu Isotope 2= 109.00 amu

Average atomic weight = 107.87 amu

F₁= 0.565

F₂= 0.435

Formula mass/percent comp

100

True/false

The percent composition of oxygen in Al₂(SO₄)₃ is 65.4%

False

200

What is the formula mass of C₇H₆Fe₄

313.4 amu

300

What is the formula mass of Ba₇H₄(N₂O)₄

1141.31 amu

400

What is the percent composition of Nitrogen in N₂O₄

30.45%

500

What is the percent composition of chromium in Cr(NO₃)₃

21.8%