Matter is neither created nor destroyed but instead is changed from one form to another
100
What did the cathode ray tubes contain inside of them that allowed the experiments to work?
Gas
100
1 mole is equal to how many particles?
6.022 E 23 (Avogadro's Number)
100
The atomic number indicates:
How many protons an element has and how many electrons a neutral element has
100
The average atomic mass of an element depends on both the masses of its isotopes and each isotope's:
A atomic number.
B radioactivity.
C percent (relative) abundance.
D mass number.
C
200
The forces that hold the particles in the nucleus together are called
Nuclear forces
200
How did the rays produced in a cathode tube in early experiments behave?
They were repelled by a negative plate
200
18 g of Carbon, C is equal to how many moles?
1.5 moles Carbon
200
The nucleus of most atoms is composed of
Tightly packed protons and neutrons
200
An isotope of mercury has 80 protons and 120 neutrons. What is the mass number of this isotope?
200
300
Dalton's atomic theory helped reinforce the law of conservation of mass because it stated that atoms
Cannot be created or destroyed
300
Rutherford's experiments led to the discovery of the
Nucleus
300
How many moles are in 14 g of Nitrogen, N?
1 mole
300
Most of the volume of an atom is occupied by the
Electron Cloud
300
Determine the mass number of isotope sulfur-33
33
400
Which concept of Dalton's was changed for the modern atomic theory?
Atoms cannot be divided
400
Because a few positively charged particles bounced back from the foil, Rutherford concluded that such particles were
Repelled by dense regions of positive charge
400
How many atoms are in 6.5 moles of Oxygen, O?
3.9 E 24 atoms
400
Why are most elements neutral in charge?
Number of protons is equal to number of electrons
400
How many protons and neutrons are in one atom of
30
Si
14
14 protons, 16 neutrons
500
According to Dalton's Theory, Atoms of the same element are
Identical in size, shape, mass, and other properties.
500
The behavior of cathode rays produced in a glass tube containing gas at low pressure led scientists to conclude that the rays were composed of
Negative charges
500
How many grams are in 6.24 E 25 atoms of Fluorine, F?
1969 g Fluorine
500
What are protons and neutrons made up of?
Quarks
500
A sample of Element X is found to contain 72.15% of isotope type 1 (84.9118 amu) and 27.85% of isotope type 2 (86.9092 amu). Calculate the average atomic mass.