Chemistry Bunco!

Round 1

»What is the name of this device?»Which

scientist used this device?

Round 1 -Answer

»Cathode Ray tube»JJ Thomson

Round 2

»What experiment did Millikan do and what was one of his conclusions?

Oil Drop ExperimentDetermined the mass of an electron (1/2000th the mass of H atom)Determined the charge on the electron (negative)

Round 3

»What experiment did Rutherford do and describe it?

Round 3 - Answer

» Rutherford did the gold foil experiment» Bombarded a thin piece of gold foil

with fast moving positively charged alpha particles» Expected the alpha particles to pass

straight through. Most did, but 1 in 8000 were deflected back.

Round 6

»Complete the table for the main subatomic particles.

Particle Relative Charge

Mass Number

Location in atom

Proton +1 1 nucleusNeutron 0 1 nucleusElectron -1 0 Outside

nucleus

Round 5

»State 3 observations that Rutherford made (what did he see) and 3 conclusions he made from those observations.

1.Most of the alpha particles passed straight through the foil – atom is mostly empty space

2.1 in 8000 particles bounced back – atom has a very tiny, dense nucleus

3.Some alpha particles deflected – nucleus has a positive charge b/c positive alpha particles are repelled

Round 5 - Answers

Round 8

»What does the atomic number represent?»The number of protons in the nucleus of each atom of that element

Round 9

»What does the mass number represent?»The number of protons + neutrons in the nucleus

Round 10

»Define isotope»Atoms of the same element that have different masses

Round 11

»How do nuclides of the same element differ from each other (be specific)?»The have a different

number of neutrons

Round 12

»Write the nuclear symbol and hyphen notation for the nuclide that has 2 protons and 2 neutrons.»Helium-4 4He

2

Round 7

»Define atom»The smallest particle of

an element that retains the chemical properties of that element

Round 13

»What nuclide is used as the standard in the relative scale for atomic masses? »What is its assigned atomic

mass?Carbon-1212 amu

Round 14

»What is the definition of the mole?

The amount of particles equal to the number of atoms in exactly 12 g of Carbon-12

Round 15

»How many particles are in one mole?

6.022x1023

Round 16

»What is the name given to the number of particles in one mole?Avogadro’s number

Round 17

»Calculate the average atomic mass of argon to 2 decimal places give the following isotopes:»Argon-36 (35.97amu; 0.337%)»Argon-38 (37.96amu; 0.063%)»Argon-40 (39.96amu; 99.600%)

39.95 amu

Round 18

»Naturally occurring boron is 80.20% boron-11 (11.01amu) and 19.80% of another isotope. The average atomic mass of boron is 10.81amu. What must the atomic mass of the second isotope be?

10.01 amu

Round 19

»How many atoms are in 6.755 mol Pb?

4.068x1024 atoms

Round 20

»How many atoms are in 0.250 mol Si?

1.51x1023 atoms

Round 21

»What is the mass in grams of 3.011x1023 atoms F?

9.499 g

Round 22

»What is the mass in grams of 25 atoms W?

7.6x10-21 g

Round 23

»Determine the number of atoms in 1.50g K.

2.31x1022 atoms

Round 24

»Determine the number of atoms in 0.02550 g Pt.

7.872x1019 atoms

Round 25

»Write the nuclear symbol and hyphen notation for the nuclide that has 6 protons and 8 neutrons.»Carbon-14 14C6

Round 26

»How many isotopes does hydrogen have? Describe them.

Round 26 - Answer

»Protium – 1 proton, 0 neutrons, 1 electron (most common)»Deuterium – 1 proton, 1

neutron, 1 electron»Tritium – 1 proton, 2 neutrons,

2 electron (radioactive)

Round 27

»What forces holds the nuclear particles together in the nucleus?»Nuclear forces

Round 28

»How did Dalton’s theory explain the law of conservation of mass?»Chemical reactions involve the

rearrangement of atoms, but atoms are not subdivided, created or destroyed.

Round 29

»How many protons, electrons, and neutrons are there in an atom of chlorine-37?»17p+; 17e-; 20n0

Round 30

»How many protons, electrons, and neutrons are there in an atom of bromine-80?»35p+; 35e-; 45n0

Round 31

»Write the hyphen notation for the element that contains 15 electrons and 15 neutrons.»Phosphorous-30

Round 32

»What is an amu?»1/12 the mass of a carbon-12 atom»Atomic mass unit

Round 33

»What is the mass in grams of 3.50 mol of the element copper?»222 g of Cu

Round 34

»The atomic mass of Tungsten is 83.84amu. What is the molar mass of Tungsten?»83.84 g/mol

Round 35

»How many atoms are in 132.90543g of Cesium?»6.022x1023 atoms of Cs

Round 36

»How many moles of calcium are in 5.00g of calcium?»0.125 mol Ca

Round 37

»How many atoms of lead are in 52.7g of lead?»1.53x1023

atoms of Pb

Round 38

»How many neutrons does uranium 238 have?»146 neutrons

Round 39

»How many protons does osmium-190 have?»76

Round 40

»What is the name of the nuclide that has 22 protons and 25 neutrons?»Titanium-47

Round 41

»Write the nuclear symbol for the isotope of sodium with mass 23 23Na11

Round 42

»A student finds that 15.20g of nitrogen will react with 17.37g, 34.74g, or 43.43g of oxygen to form three different compounds. This is an example of which law?Law of Multiple Proportions

Round 43

»State the 5 points of Dalton’s atomic theory

1. All matter is composed of atoms2. Atoms of a given element are identical in size, mass, and other

properties3. Atoms cannot be subdivided, created, or destroyed4. Atoms of different elements combine in simple whole-number

ratios to form chemical compounds5. In chemical reactions, atoms are combined, separated, or

rearranged.

Round 44

»Which aspects of Dalton’s atomic theory were incorrect?

Atoms cannot be subdivided – we know atoms are made of protons, neutrons & electrons.Atoms of a given element are identical in size, mass… - we know isotopes exist

Round 4

»Describe 4 properties of electrons that were determined based on the experiments of Thomson and Millikan.

Round 4 - Answers

1.Electron is negatively charged2.Has a mass of 1/2000th of H

atom3.Has a fixed charge to mass ratio4.Present in atoms of all elements