Chemistry 101 Chapter 4 Test

Chlorine has two stable isotopes, Cl-35 and Cl-37. If their exact masses are 34.9689 amu and 36.9695 amu, respectively, what is the natural abundance of Cl-35? (The atomic mass of chlorine us 35.45 amu)

75.95%

All of the following statements about different elements are true EXCEPT: A) Barium is an alkaline earth metal B) Sulfur is considered a metalloid C) Manganese is a transition metal D) Krypton is one if the noble gases E) Iodine is a halogen.

B) Sulfur is considered a metalloid

Which statement below accurately describes the contributions of Dalton? A) Ancient Greek philosopher who proposed that matter was continuous B) Created the modern periodic table C) Proposed the modern Atomic Theory D) Discovered the existence of electrons

C) Proposed the modern Atomic Theory

What is the charge on an ion that has an atomic number of 24 and contains 22e-?

2+

What is the charge formed on the ion formed by selenium?

2-

A fictional element named Nivadium is found to have three naturally occurring isotopes with natural abundances shown here: 22.1760-45.00% 23.1847-45.00% 24.1934-10.00% The calculated atomic mass of Nivadium is?

22.83 amu

What is the mass number of the hydrogen isotope the contains 2 neutrons?

3

How many electrons are in Br-?

36

A specific isotope of an element is known to have 15 protons and 16 neutrons. Which would properly represent this isotope?

P-31

What is the charge on the cesium ion?

1+

The atomic mass unit is defined as: A) 1/12 the mass of a carbon atom containing six protons and six neutrons B) None of the above C) The mass of electrons found in a carbon atom containing six protons and neutrons D) The mass of the hydrogen atom containing only one proton E) 1/14 the mass of a nitrogen atom containing 7 protons and 7 neutrons.

A) 1/12 the mass of a carbon atom containing six protons and six neutrons.

Group 2A elements are also called:

Alkaline Earth Metals

Which of the following is NOT part of Dalton's Atomic Theory? A) Atoms combine in simple, whole-number ratios to form compounds B) All of the above are part of the Atomic Theory C) All atoms of a given element have the same mass and other properties that distinguish them from the atoms of other elements D) Most of the atom's mass and all of its positive charge is contained in a small core called the nucleus E) Each element is composed of tiny indestructible particles called atoms

D) Most of the atoms mass and all of its positive charge is contained in a small core called the nucleus

A fictional elements has two naturally occurring isotopes with natural abundances shown here: 18-40.00% 20-60.00% Which statement is TRUE for this element? A) The atomic mass would be less than 18 B) The atomic mass would be closer to 18 than to 20 C) The atomic mass would be exactly 19 D) The atomic mass would be closer to 20 than to 18 E) The atomic mass would be greater than 20.

D) The atomic mass would be closer to 20 than to 18.

Which statement reflects the results of Rutherford's gold foil experiments? A) Almost all of the alpha particles were deflected back in the direction from which they came B) Almost all of the alpha particles sputtered gold atoms off of the surface of the foil C) None of the above D) Almost all of the alpha particles were deflected while passing through the foil E) Almost all of the alpha particles passed directly through the foil.

E) Almost all of the alpha particles passed directly through the foil.

The number of protons in the nucleus of an atom A) is called the atomic number B) is given the symbol "Z" C) identifies the atom as a particular element D) is the same for all isotopes of an element E) All of the above

E) all of the above