Tag: study of the first element - hydrogen
Questions Related to study of the first element - hydrogen
Hydrogen loses its electron to form $H^+$, in this respect, it resembles:
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halogens
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alkali metals
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transition element
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alkaline earth metals
Alkali metals are electro positive in nature it readily lose its valence shell electron, and hydrogen resembles like alkali metals.
The oxidation number of hydrogen varies from:
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-1 to +1
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0 to +1
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-1 to 0
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0 to +2
The electronic configuration of the hydrogen atom is $1s^{1}$. So, it can act as an electron acceptor to complete its' outer orbital as well as it can act as an electron donor to donate its' outermost electron to gain stability like metals.
Hydrogen is :
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electropositive
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electronegative
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both electronpositive as well as electronegative
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neither electropositive nor electronegative
Hydrogen is both electropositive as well as electronegative.
Like alkali metals, H has tendency to lose its one valency electron to form unipositive hydrogen ion $H^+$.
Hence, hydrogen is electropositive in nature.
Like halogens, hydrogen has tendency to gain one electron and form uninegative ion $H^-$.
Hence, hydrogen is electronegative in nature.
Hydrogen behaves as a metal:
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at low temperature
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at low pressure
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at high temperature
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at high pressure
Metallic hydrogen is a phase of hydrogen when it behaves as electrical conductor. At the high pressure of gigapascals hydrogen might exist as a liquid metal. Liquid metallic hydrogen is thought to be present in large amount in gravitationally compressed interiors of Jupiter and Saturn.
Why does $H^+$ always get associated with other atoms or molecules?
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Ionisation enthalpy of hydrogen resembles that of alkali metals.
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Its reactivity is similar to halogens.
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It resembles both alkali metals and halogens.
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Loss of an electron from hydrogen atom results in a nucleus of very small size as compared to other atoms or ions. Due to small size it cannot exist freely.
Hydrogen has one electron in its s orbital and it can lose its electron like alkali metals which are highly electropositive in nature for their tendency to lose single electron from its outer shell. So hydrogen is similar to alkali metals.Positive hydride ions react with oxides and hydroxides to form water and with carbonates to form water and carbon dioxide.
The usual valency of hydrogen is:
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$-2$
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$0$
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$+1 $ or sometimes $-1$
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$+2$
The electronic configuration of hydrogen is ${ 1s }^{ 1 }$ as it has only one electron in its single orbital. So, it can gain one or lose one electron from its s orbital, thereby, showing $+1$ or $-1$ valency.
Which group hydrogen has resemblance?
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I-A
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II-A
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IV-A
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VII-A
1.Resemblance of H with alkali metals-Both have one electron in its valency shell and form positive ion by losing electron.
Among I-A elements which is the only non-metal ?
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Hydrogen
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Lithium
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Sodium
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Potassium
In alkali metals hydrogen is the only non metal diatomic hydrogen gas.
The element symbol for hydrogen is:
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K
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H
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He
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Hn
Hydrogen is a chemical element with chemical symbol H and atomic no. 1 with atomic weight 1.00794 amu,hydrogen is the lightest element on the periodic table. Its monatomic form is the most abundant in nature.
Which of the following statements are not true for hydrogen?
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It exists as diatomic molecule.
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It has one electron in its outermost shell.
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It can lose electron to form a cation which can exist freely.
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It forms a large number of ionic compounds by losing an electron.
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Hydrogen has 1 electron in its outermost shell due to which it combines with other hydrogen by covalent bons and exists as diatomic molecule.
- Its ionisation enthalpy is very high due to which it does not loose electron and hence, is unable to form cation and ionic compounds. (Ionisation enthalpy is the energy required for the removal of electron from the gaseous isolated atom in its ground state.)