Chemistry, 15.12.2020 16:10 rebekahlm

When hydrogen reacts with calcium metal, what are the oxidation numbers of the calcium and hydrogen in the CaH2 product? Ca(s)+ H2(g) → CaH2

a. +2 and -1
b. +1 and -2
c. +2 and 2
d. 0 and 0
e. -2 and +1

Answers: 2

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Answers

The oxidation number of calcium has been +2, and the oxidation number of hydrogen has been -1. Thus, the correct option is A.

The oxidation number can be defined as the number of electrons that have been lost by an atom in a chemical reaction.

The oxidation number can be calculated as the:

The oxidation number of Hydrogen when it combines with the less electronegative element has been -1.

There have been 2 atoms of Hydrogen that lose an electron, thus the total oxidation contribution of hydrogen has been -2.

The oxidation number of hydrogen has been -1.

The oxidation number of Calcium has been:

Ca atom has taken an electron from the hydrogen.

$\rm Ca\;+\;e^-\;\rightarrow\;Ca^-$

The calcium takes one electron from each atom bonded. Thus the oxidation number of calcium has been +2.

The oxidation number of calcium has been +2, and the oxidation number of hydrogen has been -1. Thus, the correct option is A.

For more information about oxidation numbers, refer to the link:

link

Answer from: genyjoannerubiera

e. -2 and +1

Explanation:

Oxidation number or oxidation state : It represent the number of electrons lost or gained by the atoms of an element in a compound.

Oxidation reaction is defined as the reaction in which a substance looses its electrons. The oxidation number of the substance increases.

Reduction reaction is defined as the reaction in which a substance gains electrons. The oxidation number of the substance gets reduced.

$Ca(s)+H_2(g)\rightarrow CaH_2$

The oxidation number of calcium (Ca) in free state is 0 and in CaH_2 , it is -2.

The oxidation number of hydrogen in H_2 is zero and oxidation number of hydrogen in CaH_2 is +1 as in hydrides hydrogen loses electrons.

Answer from: Quest

B. nuclear reactions could first occur.

Answer from: Quest

Vander waals forces are inter molecular bonds that exist within molecules of the same substance. a water molecule is made up of oxygen and hydrogen atoms which share electrons between each other. the vander waals forces are forces that exist between multitude of different molecules of water. dipole dipole forces is the type of vander waals force that exist in water. the oxygen atom which is more electronegative pulls the shared electron closer to itself thus generating a partial negative charge while the hydrogen acquire a partial positive charge. these two different charges causes attraction to occur in water molecules.