Chemistry

Which of the following correctly expresses 52,030.2 m in scientific notation? a) 5.20302 x 10 4 m b) 5.20 x 10 4 m c) 5.20302 x 10 5 m d) 5.2 x 10 4 m e) 5.203 x 10 4 m

5.20302 x 10 4 m

Avoadro's number (N) or 1 mol

6.022x 10 *23rd*

Max Planck

German physicist whose explanation of blackbody radiation in the context of quantized energy emissions initiated quantum theory (1858-1947)

Law of Conservation of Matter

Matter is not created nor destroyed in any chemical or physical change

Systematic Error

Values that are either all higher or all lower than the actual value

mass percent formula

% = part/whole x 100 %

Wavelength

(A, Greek "lambda") the distance between any point on a wave to the corresponding point on the next wave expressed in units of meters.

Celsius to Fahrenheit

(C x 1.8) + 32

Fahrenheit to Celsius

(F-32)/1.8

The S.I. unit of speed (velocity) is Question options: a) km/h b) km/s c) m/h d) m/s e) none of these choices is correct

m/s

Which of the following is an extensive property of oxygen? a) boiling point b) density c) temperature d) mass e) average kinetic energy of molecules

mass

Density Formula

mass/volume

Neutrons

uncharged particles in the nucleus with mass approximately equal to a proton

JJ Thomson

used the cathode ray tube to discover electrons, plum pudding model

Which one of the following is a "substance" in the sense of the word as used in your textbook? a) air b) tap water c) sea water d) water e) toothpaste

water

Frequency

(v, Greek "nu") - the number of cycles the wave undergoes per second expressed as 1/second or s-1.

Celsius absolute zero

-273

Fahrenheit absolute zero

-460 degrees

The area of a 15-inch pizza is 176.7 in2. Express this area in square centimeters. a) 1140. cm2 b) 448.8 cm2 c) 96.8 cm2 d) 69.57 cm2 e) 27.39 cm2

1140. cm2

Acetone, which is used as a solvent and as a reactant in the manufacture of Plexiglas®, boils at 56.1°C. What is the boiling point in degrees Fahrenheit? a) 159°F b) 133°F c) 101°F d) 69.0°F e) 43.4°F

133°F

Robert Millikan

1909 oil drop experiment, calculated the charge of the electron, calculate the mass of electrons

How fast does electromagnetic radiation travel?

2.99792458 x 108 m/s or 3.00 x 108 m/s

Select the answer with the correct number of decimal places for the following sum: a) 269.01860 cm b) 269.02 cm c) 269.0186 cm d) 269.0 cm e) 269.019 cm

269.0 cm

Freezing point in kelvin

273

What is the energy of one photon with a wavelength of 590 nm?

3.37×10-19 J

Freezing point in Fahrenheit

32

Accuracy

Refers to how close a measurement is to the actual value

speed (c)

The product of a wave's frequency and its wavelength

Temperature

a measure of how hot or cold an object is

Which of the following correctly expresses 0.000007913 g in scientific notation? a) 7.913 x 10 6 g b) 7.913 x 10-6 g c) 7.913 x 10 5 g d) 7.913 x 10-9 g e) 7.913 x 10-5 g

7.913 x 10-6 g

Express 96,342 m using 2 significant figures. a) 9.60 x 10 4 m b) 9.6 x 10-4 m c) 9.6 x 10 4 m d) 96,000. m e) 9.60 ´ 10-4 m

9.6 x 10 4 m

average mass

= ∑(𝑓𝑟𝑎𝑡𝑖𝑜𝑛𝑎𝑙 𝑎𝑏𝑢𝑛𝑑𝑎𝑛𝑐𝑒)(𝑖𝑠𝑜𝑡𝑜𝑝𝑒 𝑚𝑎𝑠𝑠)

Absolute zero definition

The lowest temperature that ceases all movement of matter

You prepare 1000. mL of tea and transfer it to a 1.00 quart pitcher for storage. Which of the following statements is true? a) The pitcher will be filled to 100% of its capacity with no tea spilled. b) The pitcher will be filled to about 95% of its capacity. c) The pitcher will be filled to about 50% of its capacity. d) The pitcher will be completely filled and a small amount of tea will overflow. e) The pitcher will be completely filled and most of the tea will overflow.

The pitcher will be completely filled and a small amount of tea will overflow.

fundamental unit of charge

The smallest measured electric charge, which belongs to a single proton or electron, and is equal to 1.6x10^-19 C.

What is the frequency (in s-1) of the electromagnetic radiation from blue sky ( = 473 nm)?

6.34 x 1014 s-1

Which measurement is expressed to 4 significant figures? a) 0.00423 kg b) 24.049 cm c) 1300 K d) 82,306 m e) 62.40 g

62.40 g

A dose of medication was prescribed to be 35 microliters. Which of the following expresses that volume in centiliters? a) 3.5 ´ 105 cL b) 3.5 ´ 10-4 cL c) 3.5 ´ 104 cL d) 3.5 ´ 10-3 cL e) 3.5 cL

d) 3.5 ´ 10-3 cL

A cook uses a microwave oven to heat a meal. The wavelength of the radiation is 1.20 cm. What is the energy of one photon of this microwave radiation?

1.66 x 10 (-23) J

A flask has a mass of 78.23 g when empty and 593.63 g when filled with water. When the same flask is filled with concentrated sulfuric acid, H2SO4, its mass is 1026.57 g. What is the density of concentrated sulfuric acid? (Assume water has a density of 1.00 g/cm3 at the temperature of the measurement.) a) 1.992 g/cm3 b) 1.598 g/cm3 c) 1.840 g/cm3 d) 0.543 g/cm3 e) 1.729 g/cm3

1.840 g/cm3

Boiling point in Celsius

100

Which of the following represents the largest volume? a) 10,000 µL b) 1000 pL c) 100 mL d) 10 nL e) 10 cm3

100 mL

The S.I. prefix mega- (M) means a) 10x-6 b) 10x-3 c) 10x3 d) 10x6 e) 10x9

10x6

Boiling point in Fahrenheit

212 degrees

Ion

charged atom due to unequal numbers of protons and electrons

Electron

negatively charged particles, surround nucleus

electromagnetic radiation

energy propagated through space by means of alternating electric and magnetic fields.

Albert Einstein

explained the photoelectric effect in terms of the absorption of small bundles of electromagnetic energy. He termed these 'particles' of electromagnetic energy as light quanta.

empirical formula

indicates atoms present in compound in the simplest whole-number ratio of atoms

Atoms

indivisible particle that is the smallest unit of an element

atomic number (z)

number of protons in nucleus

The density of mercury, the only metal to exist as a liquid at room temperature, is 13.6 g/cm3. What is that density in pounds per cubic inch? a) 849 lb/in3 b) 0.491 lb/in3 c) 491 lb/in3 d) 1.83 x 10-3 lb/in3 e) 376 lb/in3

0.491 lb/in3

Iron (Fe) is the main component of steel and is therefore the most important metal in society; it is also essential in the body. How many Fe atoms are in 95.8 g of Fe?

1.04 x 1024 atoms Fe

The average distance between the Earth and the Moon is 240,000 miles. Express this distance in kilometers. a) 6.1 ´ 105 km b) 1.5 ´ 105 km c) 5.3 ´ 105 km d) 9.4 ´ 104 km e) 3.9 ´ l05 km

3.9 ´ l05 km

Boiling point of Kelvin

373

molecular formula

A chemical formula that shows the number and kinds of atoms in a molecule, but not the arrangement of the atoms.

Scientific Notation

A method of writing or displaying numbers in terms of a decimal number between 1 and 10 multiplied by a power of 10.

Density

A physical property that relates the mass of a substance to its volume.

Ammonium carbonate, (NH4)2CO3, a white solid that decomposes on warming, is an component of baking powder. a)How many molecules are in 41.6 g of ammonium carbonate? b) How many O atoms are in this sample?

A. = 2.61x10(23) molecules (NH4)2 CO(3) B.= 7.83 x 10(23) O atoms

Ernest Rutherford is credited with...

All positive charge in an atom is concentrated in a tiny, heavy nucleus located at the atom's center (Gold Foil Experiment). Also discovered the Atomic Nucleus.

Law of Definite Proportions

All samples of a pure compound contain the same elements in the same proportion by mass

Anion

An atom that gains one or more electrons will exhibit a negative charge

Cation

An atom that loses one or more electrons will exhibit a positive charge

Isotopes

Atoms of the same element that have different numbers of neutrons / have the same atomic number (# protons)

absence of a time lag

Current flows the moment light of the minimum frequency shines on the metal, regardless of the light's intensity

At the turn of the 20th century, three phenomena involving matter and light confounded physicists

Blackbody radiation, The Photoelectric Effect, Atomic Spectra

Bud N. Chemist must determine the density of a mineral sample. His four trials yield densities of 4.77 g/cm3, 4.67 g/cm3, 4.69 g/cm3, and 4.81 g/cm3. Independent studies found the correct density to be 4.75 g/cm3. Which of the following statements represents the best analysis of the data? a) Bud's results have much greater accuracy than precision. b) Bud's results have much greater precision than accuracy. c) Bud's results have high accuracy and high precision. d) Bud's results have low accuracy and low precision. e) Bud's equipment is faulty.

Bud's results have much greater accuracy than precision.

Select the best statement. a) Chemical changes provide the only valid basis for identification of a substance. b) Chemical changes are easily reversed by altering the temperature of the system. c) Chemical changes always produce substances different from the starting materials. d) Chemical changes are associated primarily with extensive properties. e) Chemical changes are accompanied by changes in the total mass of the substances involved.

Chemical changes always produce substances different from the starting materials.

Heinrich Rudolf Hertz

Discovered radio waves; unit of frequency named after him

E = n h v

E is the energy of the radiation v is its frequency n is a positive integer (1, 2, 3 and so on) called a quantum number h = 6.626 x 10-34 Js (planck's constant

Thomsons's "Plum Pudding" Atomic Model showed that...

Electrons are negatively charged particles. But matter is neutral, so atoms must also contain a positively charged component

As chief chemist at Superior Analytical Products (SAP) you must design an experiment to determine the density of an unknown liquid to three (3) significant figures. The density is of the order of 1 g/cm3. You have approximately 7 mL of the liquid and only graduated cylinders and balances are available for your use. Which of the following combinations of equipment will allow you to meet but not exceed your goal? a) Graduated cylinder with ±0.1 mL uncertainty; balance with ±0.1 g uncertainty b) Graduated cylinder with ±0.01 mL uncertainty; balance with ±0.1 g uncertainty c) Graduated cylinder with ±0.01 mL uncertainty; balance with ±0.01 g uncertainty d) Graduated cylinder with ±0.001 mL uncertainty; balance with ±0.001 g uncertainty e) Graduated cylinder with ±0.1 mL uncertainty; balance with ±0.001 g uncertainty

Graduated cylinder with ±0.01 mL uncertainty; balance with ±0.01 g uncertainty

What happened in 5th Century B.C?

Greek philosophers propose matter composed of small, finite particles called atomos (meaning indivisible)

Random Error

In the absence of systematic error, produces values that are higher and lower than the actual value

Kelvin to Celsius

K-273

Celsius to Kelvin

K=C+273

Precision

Refers to reproducibility or how close the measurements are to one another

The Electromagnetic Spectrum

We perceive different wavelengths (or frequencies) of visible light as different colors, red ( = 750 nm) to violet ( = 400 nm).

angle of refraction.

When a wave strikes a boundary (say between air and water) at any angle other than 90°, the change in speed causes a change in direction.

Law of Multiple Proportions

When two elements react to form more than one compound, a fixed mass of one element will react with masses of the other element in a ratio of small, whole numbers

cathode ray

a stream of electrons produced at the negative electrode (cathode) of a tube containing a gas at low pressure

atomic mass unit

a unit of mass that describes the mass of an atom or molecule

Diffraction

a wave striking the edge of an object will bend around it.

At a pressure of one billionth (10-9) of atmospheric pressure, there are about 2.7 ´ 1010 molecules in one cubic centimeter of a gas. How many molecules is this per cubic meter? a) 2.7 ´ 10x16 b) 2.7 ´ 10x14 c) 2.7 ´ 10x12 d) 2.7 ´ 10x8 e) 2.7 ´ 10x4

a) 2.7 ´ 10x16

Element

consists of only one type of atom, which has characteristic mass and other properties

Compound

consists of atoms of two or more elements combined in whole number ratios

polychromatic

(Greek "many colors") light - light consisting of many wavelengths.

monochromatic

(Greek "one color") light- light consisting of a single wavelength.

Freezing point in Celsius

0

Kelvin absolute zero

0 K

How many moles of pyridine (C5H5N) are contained in 3.13 g of pyridine (Molar mass 79.10 g/mol)?

0.0396 mol

The result of (3.8621 ´ 1.5630) - 5.98 is properly written as Question options: a) 0.06 b) 0.056 c) 0.0565 d) 0.05646 e) 0.056462

0.06

The average distance from Earth to the Sun is 150 megameters. What is that distance in meters? a) 1.5 ´ 108 m b) 1.5 ´ 103 m c) 1.5 ´ 106 m d) 1.5 ´ 10-6 m e) 1.5 ´ 105 m

1.5 ´ 108 m

Select the best statement. a) Physical changes may be reversed by changing the temperature. b) Physical changes alter the composition of the substances involved. c) Physical properties are not valid characteristics for identifying a substance. d) Physical properties are mostly extensive in nature. e) Physical changes are usually accompanied by chemical changes.

Physical changes may be reversed by changing the temperature.

black body radiation

an object the absorbs all electromagnetic radiation that falls on it. Classical physics predicts that a _______ will produce a continuous spectrum of visible light if it is heated to very high temperatures

Which of the following is a chemical change? a) boiling of water b) condensing water vapor into rainfall c) melting wax d) carving a piece of wood e) broiling a steak on a grill

broiling a steak on a grill

Isomers

compounds with same chemical formula but different molecular structures

Given that 1 inch = 2.54 cm, 1 cm3 is equal to a) 16.4 in3 b) 6.45 in3 c) 0.394 in3 d) 0.155 in3 e) 0.0610 in3

e) 0.0610 in3

diffraction pattern

generated when light passes through adjacent slits.

Refraction

light of a given wavelength travels at different speeds through different transparent media - vacuum, air, quartz, water, etc.

threshold frequency

light shining on the metal plate must have a minimum frequency, or no current flows AND different metals have different minimum frequencies.

Water vapor is less dense than ice because a) molecules in the gas phase are in constant motion. b) molecules in the gas phase have more potential energy than in solids. c) molecules in the gas phase have more kinetic energy than in solids. d) gaseous molecules have less mass. e) molecules in the gas phase have more space between them than in solids.

molecules in the gas phase have more space between them than in solids.

Protons

positively charged particles, reside in the nucleus

How did Thomson establish that cathode rays were composed of negative particles?

showed experimentally that the cathode ray was deflected by electric fields away from the negative electrode and toward the positive electrode.

structural formula

shows how the atoms are connected in the molecule ex: ball-and-stick , space-filling models

mole

the SI base unit used to measure the amount of a substance

photoelectric effect

the flow of electric current when monochromatic light falls on a metal plate

amplitude

the height of the crest (or the depth of the trough). Measure of the strength of a wave's electric and magnetic fields. Also related to what we perceive as light intensity.

molar mass (M)

the mass per mole of its entities (atoms, molecules or formula units)

Chemistry Definition

the study of the composition, structure, and properties of matter, the processes that matter undergoes, and the energy changes that accompany these processes

mass number (A)

the sum of the number of neutrons and protons in an atomic nucleus

Hertz

the unit of frequency, equal to one cycle per second

atomic mass

weighted average mass of its naturally occurring isotopes