Ch 4&5 Chem Quizlet

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energy levels

Fixed energies an electron can have

#49 What is the difference between mass number and the atomic number of an atom?

The atomic number is the number of protons.The mass number is the sum of the protons and neutrons

#47 What happens when a hydrogen atom absorbs a quantum of energy?

The electron of the hydrogen atom is raised (excited) to a higher energy level

#33 What is it meant by 3p^3?

The p orbitals in the third quantum level have three electrons

#34 What is an atom?

The smallest particle of an element that retains its identity in a chemical reaction

Nucleus

The tiny central core of an atom and is composed of protons and neutrons

Mass number

The total number of protons and neutrons in an atom

#40 List the colors of the visible spectrum in order of increasing wavelength.

Violet,indigo,blue,green,yellow, orange, red

amplitude

Wave's height from zero to the crest

electron configuration

Ways in which electrons are arranged in various orbitals around the nuclei of atoms

spectrum

When sunlight passes through a prism, the different frequencies separate into colors

ground state

When the electron has its lowest possible energy

#39 Write electron configurations for atoms of these elements. b - vanadium

[Ar] 4s^2 3d^3

#29 How many sublevels are contained in each of these principle energy levels? a - n=1 b - n=2 c - n=3 d - n=4

a - 1 b - 2 c - 3 d - 4

#50 Complete the following table by referring to figure 4.11 on page 118.

a - 19 b - 9 c - F d - 14 e - 29 f - Si g - 22 h - 22 i - Ti j - 25 k - 30 l - Mn

#30 How many electrons are in the highest occupied energy level of these atoms? a - barium b - sodium c - aluminum d - oxygen

a - 2 b - 1 c - 3 d - 6

#36 What is the maximum number of electrons that can go into each of the following sublevels? a - 2s b - 3p d - 3d g - 4f

a - 2 b - 6 d - 10 g - 14

#35 Which of these orbital designations are invalid? a - 4s b - 3f c - 2d d - 3d

a - valid b - invalid c - invalid d - valid

#26 What is an atomic orbital?

a region in space around the nucleus in which there is a high probability of finding an electron

#46 Why is an atom electrically neutral?

equal number of protons and electrons

#44 What is the charge, positive or negative, of the nucleus of every atom?

positive

#49 The transition of electrons from higher energy levels to the n=2 energy level results in the emission of light from hydrogen atoms. In what part of the spectrum is the emitted light, and what is the name given to this transition series?

visible spectrum, Balmer series

#53 What data must you know about the isotopes of an element to calculate the atomic mass of the element?

which isotopes exist, their masses, and their natural percent abundance

#24 Describe Rutherford's model of the atom and compare it with the model proposed by his student Niels Bohr.

In Rutherford's model, negatively charged electrons surround a dense, positively charged nucleus. In Bohr's model, the electrons are assigned to concentric circular orbits of fixed energy

photons

Light quanta

Electrons

Negatively charged subatomic particles

frequency

Number of wave cycles to pass a given point per unit of time

Atomic mass unit (amu)

One 12th of the mass of a carbon-12 atom

Protons

Positively charged subatomic particles

electromagnetic radiation

Radio waves, microwaves, infrared rays, visible light, ultraviolet waves, X-rays, and gamma rays

Atomic number

Represents the number of protons in the nucleus of an atom of that element

hertz

SI unit of cycles per second

Neutrons

Subatomic particles with no charge

#55 What is the atomic mass of an element?

The atomic mass is the weighted average of the masses of all the isotopes

#47 What does the atomic number of each atom represent?

number of protons in the nucleus

#40 How do the charge and mass of a neutron compare to the charge and mass of a proton?

the masses are the same; protons have a positive charge and neutrons are neutral

Atom

the smallest particle of an element that retains its identity in a chemical reaction

Dalton's atomic theory

1. All elements are composed if tiny indivisible particles called atoms. 2. Atoms of the same element are identical. The atoms of any one element are different from those of any other element. 3. Atoms of different elements can physically mix together or can chemically combine in simple whole-number ratios to form compounds. 4. Chemical reactions occur when atoms are separated, joined, or rearranged. Atoms of one element, however, are never changed into atoms of another element as a result of a chemical reaction.

#39 Would you expect two electrons to attract or repel each other?

repel

#34 Give electron configurations for atoms of these elements. a - Na (sodium)

1s^2 2s^2 2p^6 3s^1

#31 What are the three rules that govern the filling of atomic orbitals by electrons?

1. Electrons occupy the lowest possible energy levels 2. An atomic orbital can hold at most two electrons 3. One electron occupies each of a set of orbitals with equal energies before any pairing of electrons occurs

#37 Arrange the following sublevels in order of increasing energy. 3d, 2s, 4s, 3p

2s, 3p, 4s, 3d

#27 How many orbitals are in the 2p sublevel?

3

#38 How many electrons are in the second energy level of an atom of each element? a - chlorine

8

atomic orbital

A region of space in which there is a high probability of finding an electron

Atomic mass

A weighted average mass of the atoms in a naturally occurring sample of the element

Group

Aka family; each vertical column on the periodic table

quantum

Amount of energy required to move an electron from one energy level to another energy level

Pauli exclusion principle

An atomic orbital may describe at most two electrons

#25 What is the significance of the boundary of an electron cloud?

An electron is found 90% of the time inside this boundary

Periodic table

Arrangement of elements in which the elements are separated into groups based on set of repeating properties

#41 Why does it makes sense that if an atom loses electrons, it is left with a positive charge?

Atoms are neutral: number of pro- tons = number of electrons. Loss of an electron means that the num- ber of p+ is greater than the num- ber of e-, so the remaining particle is positively charged

Isotopes

Atoms that have the same number of protons but different numbers of neutrons

#54 How is an average mass different from a weighted average mass?

Average atomic mass is the arithmetic mean of the isotopes. Weighted average atomicmassconsidersboththemass and the relative abundance of the isotopes

#36 With which of these statements would John Dalton have agreed in the early 1800s? For each, explain why or why not. A. Atoms are the smallest particles of matter. B. The mass of an iron atom is different from the mass of a copper atom. C. Every atom of silver is identical to every other atom of silver. D. A compound is composed of atoms of two or more different elements.

Dalton would agree with all four statements because they all fit his atomic theory

#35 What were the limitations of Democritus's ideas about atoms?

Democritus's ideas were not help- ful in explaining chemical behavior because they lacked experimental support

quantum mechanical model

Determines the allowed energies an electron can have and how likely it is to find the electron in various locations around the nucleus

wavelength

Distance between the crests

Period

Each horizontal row of a periodic table

Hund's rule

Electrons occupy orbitals of the same energy in a way that makes the number of electrons with the same spin direction as large as possible

aufbau principle

Electrons occupy the orbitals of lowest energy first

atomic emission spectrum

Frequencies of light emitted by an element separate into discrete lines

#41 What is meant by the frequency of a wave? What are the units of frequency? Describe the relationship between frequency and wavelength.

Frequency is the number of wave cycles that pass a given point per unit time. Frequency is the number of wave cycles that pass a given point per


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