Chemistry 4.3- Lentz

How is the number of neutrons in the nucleus of an atom calculated? Select one: a. Subtract the number of protons from the mass number. b. Add the number of electrons and protons together. c. Add the mass number to the number of electrons. d. Subtract the number of electrons from the number of protons.

A. subtract the number of protons from the mass number

How is the periodic table organized?

It is organized left-to-right and top-to-bottom by increasing atomic number

All atoms are Select one: a. neutral, with the number of protons equaling the number of electrons. b. negatively charged, with the number of electrons exceeding the number of protons. c. neutral, with the number of protons equaling the number of electrons, which is equal to the number of neutrons. d. positively charged, with the number of protons exceeding the number of electrons.

a. neutral, with the number of protons equaling the number of electrons.

The atomic number of an element is the total number of which particles in the nucleus? Select one: a. protons b. electrons c. neutrons d. protons and electrons

a. protons

The atomic mass of an element is the ____. Select one: a. weighted average of the masses of the isotopes of the element b. total mass of the isotopes of the element c. total number of subatomic particles in its nucleus d. average of the mass number and the atomic number for the element

a. weighted average of the masses of the isotopes of the element

the smallest particle of an element that retains the properties of that element

atom

The _____________ of an element is the weighted average mass of the isotopes of that element

atomic mass

What does amu stand for?

atomic mass unit

the number of protons in the nucleus of an atom

atomic number

How many protons, electrons, and neutrons does an atom with atomic number 50 and mass number 125 contain? Select one: a. 70 neutrons, 75 protons, 50 electrons b. 50 protons, 50 electrons, 75 neutrons c. 120 neutrons, 50 protons, 75 electrons d. 75 electrons, 50 protons, 50 neutrons

b. 50 protons, 50 electrons, 75 neutrons

The atomic mass of an element depends upon the Select one: a. relative abundance of protons in that element. b. mass and relative abundance of each isotope of that element. c. mass of each isotope of that element. d. mass of each electron in that element.

b. mass and relative abundance of each isotope of that element

All atoms of the same element have the same ____. Select one: a. number of neutrons b. number of protons c. mass numbers d. mass

b. number of protons

Isotopes of the same element have different Select one: a. numbers of electrons. b. numbers of neutrons. c. atomic numbers. d. numbers of protons.

b. numbers of neutrons

The nucleus of an atom is Select one: a. negatively charged and has a low density. b. the central core and is composed of protons and neutrons. c. negatively charged and has a high density. d. positively charged and has more protons than neutrons.

b. the central core and is composed of protons and neutrons

An element has an atomic number of 76. The number of protons and electrons in a neutral atom of the element are ____. Select one: a. 76 protons and 0 electrons b. 152 protons and 76 electrons c. 76 protons and 76 electrons d. 38 protons and 38 electrons

c. 76 protons and 76 electrons

Isotopes of the same element have different Select one: a. atomic numbers. b. positions on the periodic table. c. mass numbers. d. chemical behavior.

c. mass numbers

The mass number of an element is equal to ____. Select one: a. less than twice the atomic number b. a constant number for the lighter elements c. the total number of protons and neutrons in the nucleus d. the total number of electrons in the nucleus

c. the total number of protons and neutrons in the nucleus

How is atomic mass calculated?

calculated by multiplying each isotope's percent abundance by its atomic mass and then adding the products

Isotopes containing ______ ________have a greater mass

more neutrons

a subatomic particle with no charge

neutron

the central part of an atom, containing protons and neutrons

nucleus

How do you find the number of neutrons if you are given the atomic number and the mass number?

number of neutrons= mass number- atomic number

How do the isotopes hydrogen-1 and hydrogen-2 differ? Select one: a. Hydrogen-2 has one neutron; hydrogen-1 has none. b. Hydrogen-2 has one proton; hydrogen-1 has none. c. Hydrogen-2 has two protons; hydrogen-1 has one. d. Hydrogen-2 has one more electron than hydrogen-1.

A. Hydrogen-2 has one neutron; hydrogen-1 has none

What must the number of protons and electrons be and why?

The number of protons and electrons in an atom must be equal because all atoms are neutral

In which of the following sets is the symbol of the element, the number of protons, and the number of electrons given correctly? Select one: a. Cs, 55 protons, 132.9 electrons b. Zn, 30 protons, 60 electrons c. F, 19 protons, 19 electrons d. In, 49 protons, 49 electrons

d. In, 49 protons, 49 electrons

The particles that are found in the nucleus of an atom are ____. Select one: a. electrons only b. protons and electrons c. neutrons and electrons d. protons and neutrons

d. protons and neutrons

a negatively charged subatomic particle

electron

atoms with the same number of protons, but different numbers of neutrons in the nucleus of the atom

isotope

the total number of protons and neutrons in the nucleus of an atom

mass number

the weighted average of the masses of the isotopes of an element

mass number

Each isotope of an element is identified with a number called the ___________ which is?

mass number; the sum of the atomic number and neutrons in the nucleus

Mass number formula:

mass number= atomic number + number of neutrons

a positively charged subatomic particle

proton

What is chemical behavior determined by?

the number of electrons an atom has

Atomic Number

the number of protons in an atom