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Chemical Reactions of Hydrogen with Other Elements
General Equation Comments
MH or MH 2 MOH or M ( OH ) 2 + H 2 ionic hydrides with group 1 and Ca, Sr, and Ba
H 2 + C (no reaction)
3H 2 + N 2 2NH 3 requires high pressure and temperature; low yield
2H 2 + O 2 2H 2 O exothermic and potentially explosive
H 2 + S H 2 S requires heating; low yield
H 2 + X 2 2HX X = F, Cl, Br, and I; explosive with F 2 ; low yield with I 2

Reaction with compounds

Hydrogen reduces the heated oxides of many metals, with the formation of the metal and water vapor. For example, passing hydrogen over heated CuO forms copper and water.

Hydrogen may also reduce the metal ions in some metal oxides to lower oxidation states:

H 2 ( g ) + MnO 2 ( s ) Δ MnO ( s ) + H 2 O ( g )

Hydrogen compounds

Other than the noble gases, each of the nonmetals forms compounds with hydrogen. For brevity, we will discuss only a few hydrogen compounds of the nonmetals here.

Nitrogen hydrogen compounds

Ammonia, NH 3 , forms naturally when any nitrogen-containing organic material decomposes in the absence of air. The laboratory preparation of ammonia is by the reaction of an ammonium salt with a strong base such as sodium hydroxide. The acid-base reaction with the weakly acidic ammonium ion gives ammonia, illustrated in [link] . Ammonia also forms when ionic nitrides react with water. The nitride ion is a much stronger base than the hydroxide ion:

Mg 3 N 2 ( s ) + 6H 2 O ( l ) 3Mg ( OH ) 2 ( s ) + 2NH 3 ( g )

The commercial production of ammonia is by the direct combination of the elements in the Haber process    :

N 2 ( g ) + 3H 2 ( g ) catalyst 2NH 3 ( g ) Δ H ° = −92 kJ
A ball-and-stick model shows a nitrogen atom single bonded to three hydrogen atoms. There is a lone pair of electron dots that appears above the nitrogen atom.
The structure of ammonia is shown with a central nitrogen atom and three hydrogen atoms.

Ammonia is a colorless gas with a sharp, pungent odor. Smelling salts utilize this powerful odor. Gaseous ammonia readily liquefies to give a colorless liquid that boils at −33 °C. Due to intermolecular hydrogen bonding, the enthalpy of vaporization of liquid ammonia is higher than that of any other liquid except water, so ammonia is useful as a refrigerant. Ammonia is quite soluble in water (658 L at STP dissolves in 1 L H 2 O).

The chemical properties of ammonia are as follows:

  1. Ammonia acts as a Brønsted base, as discussed in the chapter on acid-base chemistry. The ammonium ion is similar in size to the potassium ion; compounds of the two ions exhibit many similarities in their structures and solubilities.
  2. Ammonia can display acidic behavior, although it is a much weaker acid than water. Like other acids, ammonia reacts with metals, although it is so weak that high temperatures are necessary. Hydrogen and (depending on the stoichiometry) amides (salts of NH 2 ) , imides (salts of NH 2− ), or nitrides (salts of N 3− ) form.
  3. The nitrogen atom in ammonia has its lowest possible oxidation state (3−) and thus is not susceptible to reduction. However, it can be oxidized. Ammonia burns in air, giving NO and water. Hot ammonia and the ammonium ion are active reducing agents. Of particular interest are the oxidations of ammonium ion by nitrite ion, NO 2 , to yield pure nitrogen and by nitrate ion to yield nitrous oxide, N 2 O.
  4. There are a number of compounds that we can consider derivatives of ammonia through the replacement of one or more hydrogen atoms with some other atom or group of atoms. Inorganic derivations include chloramine, NH 2 Cl, and hydrazine, N 2 H 4 :

Questions & Answers

is methane a molecule
Okologwu Reply
calculations for solubility
malachi Reply
Whats d IUPAC Numenclature of bromine
Emmanuel Reply
The common name is therefore propyl bromide . For the IUPAC name , the prefix for bromine (bromo) is combined with the name for a three-carbon chain (propane), preceded by a number identifying the carbon atom to which the Br atom is attached, so the IUPAC name is 1-bromopropane.
What is Quantum number
Derick Reply
what are the chemical properties of group IIA Element and their atomic structure?
What is mixture
Azeez Reply
A mixture is a mix of substances that can be separated
what is quantum number
Baba Reply
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h20 hydrates, nitrogen/dry ice lowers pressure similar to space environment when heated at what location/temp.? +or-, expect location (xyz)
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what's neuron?
Kelvin Reply
neuron or neutron?
cell of the nerve
prepare a solution of 1m iodine in 250mls of water
Dj Reply
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Chemistry is the study of matter
chemistry is the study of matter and changes it undergoes
what is equilibrium
Fatai Reply
what is biology
biology is said to be the science of studying life and living organism including theirs physical structure,chemical processes, molecular interaction development and evolution
atomic number of sodium
that'll be 11
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re u writing jamb
please, how man Bond are present when a methane under goes a complete combustion
moses Reply
Combustion of Methane The reactants are on the left side of the equation and the products are on the right. In the reaction, the bonds in the methane and oxygen come apart, the atoms rearrange and then re-bond to form water and carbon dioxide.
how is ethanol produced using ethene
Ethanol is manufactured by reacting ethene with steam. The reaction is reversible, and the formation of the ethanol is exothermic. Only 5% of the ethene is converted intoethanol at each pass through the reactor
Ethanol can be made by reacting ethene (from cracking crude oil fractions) with steam. A catalyst of phosphoric acid is used to ensure a fast reaction. Notice that ethanol is the only product. The process is continuous – as long as ethene and steam are fed into one end of the reaction vessel, ethano
the mole concerpt and its tricks
Mary Reply
what are atoms
ola Reply
the individual elements of matter.
tiny particles that make up a all matter.
smallest particles of an element
What is the meaning of hybridization
Differentiate between latent heat and specific latent heat of fusion and vaporization
Amos Reply
Ans: The amount of heat energy released or absorbed when a solid changing to liquid at atmospheric pressure at its melting point is known as the latent heat of fusion. while Vaporization of an element or compound is a phase transition from the liquid phase to vapor.
Practice Key Terms 3

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