Semester 1 Final Whiteboard Review!

d. 101 °F _____________________

Identify the following data as being qualitative or quantitative: d. 101 °F _____________________

d. 101 °F _____________________

Identify the standard SI units for the following quantities:

d. 101 °F _____________________

Identify the following measurements as being accurate, precise, both, or neither: a. The actual mass is 6 g and the experimental measurements are 3.01g, 2.99g, 3.00g

precise b. The actual length is 4.50cm and the experimental measurements are 4.49cm, 4.51cm, 4.48cm

both c. The actual temperature is 23 °C and the neither experimental measurements are 32 °C, 18°C, 37°C

d. 101 °F _____________________

How many significant figures are in each of the following measurements?

What is the equation for density?

D = M/V

A sample of Aluminum metal has a mass of 8.40g. The volume of the sample is 3.1cm

3 . Calculate the density .

D = M/V = 8.40g/3.1cm

3 = 2.7097g/cm 3  2.7g/cm 3

The density of aluminum is 2.7 g/cm 3 . You have a sample that weighs 8.4 grams. What is the volume of your sample?

D = M V V = M = 8.4 g D 2.7 g/cm 3 = 3.1 cm 3

What is the name for the ratios we use to convert between one unit to another?

Conversion factors!

Show your work to convert 5.712 kilograms to milligrams. Circle the conversion factors you use.

5.712 kg x 1000 g x 1000 mg = 5,712,000 mg 1 kg 1 g

You find 13,406,190 pennies. If each penny weighs 4 grams, how much did all that loot weigh (in pounds)? (2.2 Pounds = 1 Kilogram)

13406190 pennies x 4 g x 1 kg x 2.2 pounds = 1penny 1000 g 1 kg 117,974.5 pounds

What is the relationship between frequency and wavelength for EM radiation?

c = λ ν c = wavelength * frequency

What is the frequency of light with a wavelength of 4.257 x 10 -7 cm?

c = wavelength * frequency frequency = 3.0 x 10 8 m/s = 7.047 x 10 16 4.257 x 10 -9 m Hz

What is the relationship between the frequency of light and the energy it contains?

E = h ν or E = hc/ λ h = Planck’s constant 6.626x10

-34 J s Note: this is the energy of a single photon of light of frequency ν.

If gamma radiation from cobalt-60 (used in nuclear medicine) has a wavelenghth of 1.00 x 10 -3 nm, what is the energy of a photon of this radiation?

E = hc/ λ = 6.626x10

-34 J*s x 3.00x10

8 m/s = 1.00 x 10 -12 m = 1.99 x 10 -13 J

If gamma radiation from cobalt-60 (used in nuclear medicine) has a wavelenghth of 1.00 x 10 -3 nm, what is the energy given off by a mole of cobalt-60?

E = hc/ λ = 6.626x10

-34 J*s x 3.00x10

8 m/s = 1.00 x 10 -12 m 1.9878 x 10 -13 J x 6.022 x 10 23 1 photon 1 mole photons = 1.20x10

11 J/mol

What is the energy in joules of a photon whose frequency is 3.55 x 10 17 Hz?

E = hv = 6.626x10

-34 J*s x 3.55x10

17 1/s = 2.35 x10 -16 J

How long would it take a radio wave with a frequency of 7.25 x 10 5 Hz to travel from Mars to Earth if the distance between the two planets is approximately 8.00 x 10 7 km?

8.00 x 10 7 km x 1000 m x 1 s = 267 seconds 1 km 3.0 x 10 8 m

Compare the frequency, wavelength, energy and speed of gamma rays and radio waves

Frequency Wavelength Energy Speed Gamma rays Higher frequency Radio waves Lower frequency Smaller wavelength Longer wavelength Higher energy Same (c) Lower energy Same (c)

What is the formula for calculating percent error?

%Error = actual value – experimental value actual value X 100%

A student measures the mass of a sample to be 10.26 grams, but the actual mass is 9.88 grams. What is their percent error?

% error = (9.88 - 10.26) x 100% = -3.85% 9.88

A student measures the mass of a sample to be 2.04 grams, but the actual mass is 3.20 grams. What is their percent error?

% error = (3.20 – 2.04) x 100% = 36.25% 3.20

Atoms of the same element with a different mass are called...

Isotopes!

You have an element with a mass number of 120 and has 70 neutrons. What element do you have?

120 70 = 50 protons → Tin! (Sn)

What is the most common isotope of Chromium? How many neutrons does it have?

Chromium - 52, 28 neutrons

Element X has three isotopes: one has a mass of 60.5 amu and is 78% abundant. Another has a mass of 62.4 and is 19.5% abundant. And the third has a mass of 64.7 and is 2.5% abundant. What is the average atomic mass of Element X?

60.5(0.78) + 62.4(0.195) + 64.7(0.025) = 61.0 amu

Find the molar mass of Chlorine.

35.45 g/mol

Find the molar mass of CO 2

12.01 + 2(16) = 44.01 g/mol

If you have 18 grams of Beryllium, how many moles do you have?

18 grams x 1 mole = 2 moles 9 grams

If you have 3.0 moles of carbon, how many atoms do you have?

3 moles x 6.022 x 10 23 atoms = 1.8 x 10 24 1 mole atoms

If you have 12 grams of Magnesium how many atoms do you have?

12 g Mg x 1 mol x 6.022 x 10 23 24.31 g 1 mol atoms= 3.0 x 10 23 atoms

What is the molar mass of ethanol C 2 H 6 O?

2 x 12.01 + 6 x 1.01 + 16 = 46.08 g/mol

If you have 26 grams of NaCl, how many moles do you have?

Molar mass = 23 + 35.45 = 58.45 g/mol 26 g NaCl x 1 mol = 0.44 mol 58.45 g

This is the distance between corresponding points on adjacent waves.

Wavelength!

Name the branch of chemistry that identifies the components and composition of materials.

Analytical chemistry

Name the branch of chemistry that uses mathematics and computers to design and predict the properties of new compounds.

Theoretical chemistry

Name the type of research done to solve a problem

Applied Research

What is the smallest unit of an element that maintains the properties of that element?

An atom!

What is the definition of matter? And give an example of something that is NOT matter.

Anything that has mass and takes up space. → Energy is not matter!

Give an example of an EXTENSIVE PROPERTY.

Volume, mass, amount of energy, size, etc.-- depend on the amount of matter present

What state of matter has a definite volume but indefinite shape?

Liquid!

Give an example of a chemical property.

reactivity with air, water, oxygen, etc.

Is carbon dioxide subliming (turning from solid to gas) an example of a physical or chemical change?

Physical change!

Give an example of a chemical change.

Iron rusting Coal burning Hydrogen and oxygen combining to make water

In the following reaction, what are the reactants?

Fe + O 2 → Fe 2 O 3

Fe and O 2

A solution is an example of what kind of mixture?

Homogeneous mixture! Composition is uniform throughout the mixture

A tossed salad is an example of what kind of mixture?

Heterogeneous mixture – the composition of the mixture differs throughout the mixture.

Every sample of a _________ has exactly the same characteristics and composition.

Pure substance

True or False: A compound is a pure substance.

TRUE!!! An element is also a pure substance

Vertical columns in the periodic table are called ________.

Groups!

These elements are solid, ductile and conduct electricity and heat well.

Metals!

Platinum is a member of this family of elements.

Transition metals

These elements surround the stair step on the periodic table and have a mix of properties between metals and nonmetals.

Metalloids

This group of elements are the most reactive metals on the periodic table.

Alkali metals!

What is the most reactive metal on the periodic table?

Francium! Reactivity of metals increases as you go down the group.

This group of elements are the most reactive non-metals on the periodic table.

Halogens.

What is the most reactive nonmetal on the periodic table?

Fluorine! Reactivity of nonmetals increases as you go up the group.

What is the element symbol for Mercury?

Hg

How many meters are in a Megameter?

1,000,000 or 1 x 10 6

How many micrometers are in a meter?

1,000,000 or 10 6

Give an example of a derived unit

Density, volume, molar mass, energy

The following illustrates what law?

C + O → CO or C + O 2 → CO 2

Law of multiple proportions: If two or more different compounds are composed of the same two elements, then the ratio of the masses of the second element combined with a certain mass of the first element is always a ratio of small whole numbers.

What was determined from Millikan’s oil drop experiment?

Charge and mass of an electron

Atoms of an element have the same...

Atomic number or # of protons

What phenomena gives evidence that light acts as a particle?

The photoelectric effect

Draw a picture illustrating Bohr’s model of the atom and how it relates to flame colors and atomic spectra.

What is the name for a 3 dimensional space around the nucleus where an electron may be found?

Orbital!

How many orbitals are in the 4th energy level?

16

Draw the correct orbital notation for Phosphorus.

Write the full electron configuration for Strontium (Sr) How many valence electrons does it have?

1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 2 valence electrons in the 5s subshell (electrons in the highest occupied energy level)!

Use the noble gas shortcut to write the configuration for Lead. How many valence electrons does it have?

[Xe]6s 2 4f 14 5d 10 6p 2 4 valence electrons! (only count the electrons in the highest occupied energy level, n=6)

How many valence electrons does Germanium have?

4 valence electrons!