U2.Atomic Theory_H

The sample emission spectra above represents two elements in a mixture. Which pairing would create

this emission spectra.

• A and C

• B and C

• A and B

• B and D

If an element has an atomic number of 10 and a mass number of 20, an isotope of this element must

have

• charged ions

• atoms containing more than 10 electrons

• an atomic mass greater than 20

• 10 protons in each atom

The element mercury has the atomic number 80. How many protons and electrons are in a Hg2+ ion?

• 80 protons and 200 electrons

• 80 protons and 80 electrons

• 80 protons and 78 electrons

• 80 protons and 82 electrons

Which of the following is NOT a postulate in Dalton's atomic theory?

• All matter consists of divisible particles called atoms.

• Atoms of the same element are identical in mass and properties.

• Atoms cannot be created or destroyed.

• Compounds are formed by a combination of two or more different kinds of atoms

Which of the scientists is correctly paired with the discovered subatomic particle?

1.Bohr; protons

2.Thomson; electron

3.Chadwick; neutrons

4. Rutherford; nucleus

• 3,4

• 1,2,4

• 2,3,4

• 2,3

Which of the following includes correct pairing between an atom and its number of valence electrons?

• Be,4

• Ca,2

• Al,5

• P,15

In the Gold Foil Experiment, which pathway did the least number of alpha particles follow?

• Path 1

• Path 2

• Path 3

• Path 4

The isotopes of hydrogen are hydrogen-1, hydrogen-2, and hydrogen-3. Which subatomic

particle(s) is/are found in each one of these isotopes of hydrogen?

• a neutron

• a proton, a neutron, and a electron

• a proton only

• a proton and an electron

Which scientist determined that almost all of an atom’s mass is located in its nucleus?

• Dalton

• Democritus

• Rutherford

• Thomson

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

• anion

• Atom

• cation

• mixture