CP CHEM TEST 1

Sig Figs

100

The number 145 has how many Sig figs?

3

200

Leading decimals are counted when figuring out Sig figs. True or False?

False

300

Trailing zeros never count when figuring out Sig figs. True or False?

False. They count when there is a decimal in the number.

400

The number 140.0 has how many Sig figs?

4

500

The number 0.000732000 has how many Sig figs?

6

Conversions

100

When doing conversions, what is the acronym we use?

KHDBdcm 

(King Henry Died By drinking chocolate milk)

200

Convert 5000 decameters (dam) to meters (m).

50,000 meters

300

You can go straight from any unit to another unit, even if it is above or below the base. True or False?

TRUE

400

Convert 1000 centimeters (cm) to kilometers (km)

0.01 km

500

Convert 0.005 millimeters (mm) to hectometers (hm). ANSWER IN SCIENTIFIC NOTATION

5 x 10^-8 hm

0.00000005 

Atomic Theory

100

This person referred to the atoms as "atomos"

Democritus 

200

The electron cloud model has one person who discovered it but we do not learn about that scientist in chemistry. TRUE OR FALSE? 

False. There were many contributors to electron cloud theory. That is why we do not say it was one person. 

300

This person discovered that the atom was mostly empty space

Rutherford

400

Thompson's model was labeled as the: 

Plum Pudding Model

500

This person stated that the electrons travel on fixed orbital paths

Bohr

Atomic Structure (I)

100

This number, found on the periodic table, indicates the number of protons in an atom and defines the element's identity.

Atomic Number

200

If an atom has 15 protons, 16 neutrons, and 15 electrons, this is its atomic number.

15

300

In a neutral atom, the number of electrons is always equal to the number of these.

Protons

400

To calculate the number of these subatomic particles, you subtract the atomic number from the mass number.

neutrons

500

An isotope of Carbon has a mass number of 14. Given that Carbon’s atomic number is 6, this is the number of neutrons in the atom.

8

Atomic Structure (II)

100

This value is the sum of protons and neutrons in the nucleus of a single atom.

Mass Number

200

This value, usually written as a decimal on the periodic table, is the weighted average of all naturally occurring isotopes of an element.

Average Atomic Mass

300

If a neutral Oxygen atom gains two electrons to become an ion, this is the total number of electrons it now possesses.

10

400

Chromium-54

Protons=    

Neutrons=   

Electrons=   

Atomic # =   

Mass # =    

Protons = 24 

Neutrons = 30 

Electrons = 24

Atomic # = 24 

Mass # = 54

500

carbon-12, carbon-13, and carbon-14 are all examples of what?

Isotopes