If two identical waves are in phase when they interact, the result is destructive interference

As the energy of a photon decreases, the frequency decreases and wavelength increase

Green light has a longer wavelength than microwaves

Diffraction demonstrates the wave of nature of light

According to Hund's rule, no two electrons in an atom can have the same four quantum numbers

In a multi-electron atom, all orbitals within a given subshell are degenerate

The ground-state electron configuration for Sn is [Kr] 5s^24d^105p^2

For the ground-state orbital diagram of Se, there are 4 unpaired electrons

CaCl2 dissolved in water is considered a homogenous mixture

Dimethyl ether, CH3OCH3, is considered a pure substance, molecule, and a compound

Chlorine gas, Cl2, is considered a pure substance, molecule, and compound

Sweet tea with ice cubes is considered a homogenous mixture

A valence electron in its ground state in In (Indium) could have the quantum numbers n=4, l=2, ml=1, ms= 1/2

F has 7 valence electrons, 1 of which is unpaired

Ca and Cd have the same number of valence electrons

Co has 2 valence electrons and 25 core electrons

A theory is a tentative explanation of observations; a law is model for the way nature works

A law describes why or how something happens; a theory describes what happens in nature

A law is a brief statement that summarizes past observations and predicts future ones

When iron rusts in a closed container, the mass of the container and its contents do not change” is an example of an observation

Alkali metal

Main-group metal

Nonmetal

Halogen

The law of multiple proportions applies when comparing two samples of CH2O obtained from different sources

The law of definite proportions applies when comparing a sample of CH20 to a sample of C2H4O

According to the law of conservation of mass, if 7.7 grams sodium reacts completely with 11.9 grams chlorine gas to produce sodium chloride, then 19.6 grams sodium chloride should be produced

According to the law of definite proportions, all samples of a given compound, regardless of their source or how they were produced, have the same proportions of their constituent elements 

According to the Bohr model of the atom, electrons orbit the nucleus at a particular distance, which corresponds to the energy of the electron

The energy of an electron in an atom is quantized, which means only certain values of energy are possible for an electron in an atom

In the Bohr model of the atom, when an electron absorbs energy it jumps to a lower energy level; when it jumps back to a higher energy level, it emits a photon with an energy equal to the difference

As the energy of a photon decreases, the wavelength decreases and the frequency increases

N=5, l=0, ml= -1, ms=1/2, is a valid set of quantum numbers

An electron with the quantum numbers n=3, l=2, ml=1, ms=1/2, and an electron with the quantum numbers n=3, l=1, ml=1, ms=-1/2atre in the same subshell

There are exactly 5 orbitals in an atom that can have the quantum numbers n=4, l=2

The principal quantum number corresponds to the size and energy of an orbital; the angular momentum quantum number corresponds to the shape of the orbital

Two atoms of the same element must have the same mass number

A cation is formed when a neutral atom of an element loses one or more electrons

A neutral atom of Se-80 has 34 protons, 34 electrons, and 46 neutrons

Two isotopes of an element have the same number of neutrons, but a different number of protons

Ice melting to form water is an endothermic process

Density is an intensive property; mass and volume are extensive properties

If a salt is dissolved in water and the sodium gets colder, the dissolving process is endothermic

If energy transferred from the system to the surroundings, it is a negative change in energy  for the surroundings and a positive change in energy for the system

Sn4+

Zn2+

V3+

Si

In CH3CHO, the O atom is bonded to the C and there is one double bond in the Lewis structure

There is one triple bond in C2H2

There is at least one double bond in hypochlorite

There is a triple bond in N2H2

The effective nuclear charge of Cl is larger than the effective nuclear charger of Ca

A neutral Cl atom is larger than a neutral Ca atom

Ca2+ is larger than a neutral Ca atom

Cl- is larger than a Ca2+

I has a more exothermic electron affinity than Rb

Xe has a more exothermic electron affinity than I

K has a more exothermic electron affinity than Rb

Cu has more metallic character than Rb

There are 3 equally good resonance structures

Looking at the best resonance structure (if there is more than one equally good "best" resonance structure, choose one), there is one single bond and three double bonds

Looking at the best resonance structure (if there is more than one equally good "best" resonance structure, choose one), all oxygen atoms have a 0 formal charge

Looking at the best resonance structure (if there is more than one equally good "best" resonance structure, choose one), there is a 0 charge on the bromine atom

A theory is a tentative explanation of observation; a law is a model for the way nature works

A law describes why of how something happens; a theory describes what happens in nature

A law is a brief statement that summarizes past observations and predicts future ones

"When iron rusts in a closed container, the mass of the container and its contents do not change" is an example of an observation

In CH3CHO, the O atom is bonded to the C and there is one double bond in the Lewis structure

There is one triple bond in C2H2

There is at least one double bond in hypochlorite

There is a triple bond in N2H2

The effective nuclear charge of Cl is larger than the effective nuclear charge of Ca

A neutral Cl atom is larger than a neutral Ca atom

Ca2+ is larger than a neutral Ca atom

Cl- is larger than Ca2+

The molecular geometry around the bolded atom is trigonal planar: NHCH2CNNH

The molecular geometry around the bolded atom is trigonal pyramidal: NH2CH2CNNH

The molecular geometry around the bolded atom is trigonal pyramidal: NH2CH2CNNH

The molecular geometry around the bolded atom is bent: NH2CH2CNNH

To transition from liquid to gas, you can decrease temperature or decrease pressure

Intermolecular forces between particles in a gas are very weak relative to thermal energy

Solids can be categorized as crystalline or amorphous; crystalline solids have no long-range order

In a solid, the particles cannot move with respect to one another (only vibrate in one place), so solids have a definite shape and definite volume

Nitrogen is more electronegative than boron

Sulfur is more electronegative than O

A Si-F bond would be more polar than a N-F bond

Electronegativity is the energy released when an electron is added to a gaseous atom or ion

The empirical and molecular formulas can be the same for a compound

The formula for the compound formed between Zn and Br is ZnBr

In PbS2, lead has a 2+ charge

In ionic bonding, electrons are transferred; in covalent bonding, electrons are shared

The bond between the carbon and nitrogen in CH3NH2 is longer and weaker than the bond between the carbon and nitrogen in CH2NH

There is a double bond between the carbon and nitrogen atoms in CH3NH2

There is a total of two lone pairs of electrons in CH2NH

There is a 0 formal charge on the nitrogen atom in CH2NH

Ba2I IS barium iodide

AgBrO4 is silver perbromate

CrPO4 is chromium (III) phosphate

Na2SO4 (10 H2O) is sodium sulfate decahydrate

The second ionization energy is the energy required to remove an electron from a 1+ gaseous atom

The first ionization energy of Cs is larger than the first ionization energy of Ba

The second ionization energy of Ba is smaller than the second ionization energy of Cs

The first ionization energy of Na is smaller than the first ionization energy of Cs