Tag: chemistry

Questions Related to chemistry

The element having no neutron in the nucleus of its atom is:

chemistry study of the first element - hydrogen position of hydrogen in the periodic table hydrogen in periodic table trends in groups and periods

  1. hydrogen

  2. nitrogen

  3. helium

  4. boron

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Correct Option: A
Explanation:

Hydrogen has atomic number 1. It has monatomic form is the most abundant chemical substance and it has single proton and zero neutrons. It exists in diatomic form.

Hydrogen loses its electron to form $H^+$, in this respect, it resembles:

chemistry study of the first element - hydrogen position of hydrogen in the periodic table hydrogen in periodic table trends in groups and periods

  1. halogens

  2. alkali metals

  3. transition element

  4. alkaline earth metals

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Correct Option: B
Explanation:

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:

chemistry study of the first element - hydrogen position of hydrogen in the periodic table hydrogen in periodic table trends in groups and periods

  1. -1 to +1

  2. 0 to +1

  3. -1 to 0

  4. 0 to +2

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Correct Option: A
Explanation:

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.


In hydrides like$NaH$, $H$ occurs in $-1$ state.
In acids as well as oxides, $H$ occurs in $+1$ state.

Therefore its' oxidation state varies from $-1$ to $+1$.

Hydrogen is :

chemistry study of the first element - hydrogen position of hydrogen in the periodic table hydrogen in periodic table trends in groups and periods

  1. electropositive

  2. electronegative

  3. both electronpositive as well as electronegative

  4. neither electropositive nor electronegative

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Correct Option: C
Explanation:

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:

chemistry study of the first element - hydrogen position of hydrogen in the periodic table hydrogen in periodic table trends in groups and periods

  1. at low temperature

  2. at low pressure

  3. at high temperature

  4. at high pressure

Show answer
Correct Option: D
Explanation:

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? 

chemistry study of the first element - hydrogen position of hydrogen in the periodic table hydrogen in periodic table trends in groups and periods

  1. Ionisation enthalpy of hydrogen resembles that of alkali metals.

  2. Its reactivity is similar to halogens.

  3. It resembles both alkali metals and halogens.

  4. 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.

Show answer
Correct Option: D
Explanation:

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:

chemistry study of the first element - hydrogen position of hydrogen in the periodic table hydrogen in periodic table trends in groups and periods

  1. $-2$

  2. $0$

  3. $+1 $ or sometimes $-1$

  4. $+2$

Show answer
Correct Option: C
Explanation:

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?

chemistry study of the first element - hydrogen position of hydrogen in the periodic table hydrogen in periodic table trends in groups and periods

  1. I-A

  2. II-A

  3. IV-A

  4. VII-A

Show answer
Correct Option: A,C,D
Explanation:

1.Resemblance of H with alkali metals-Both have one electron in its valency shell and form positive ion by losing electron.

2. Resemblance of H with IV group - Both have half filled valence shell. I.P. and E.A of both are comparable.
3. Resemblance of H with VII group- Both have one electron in valence shell and form anion by gaining electron.

Among I-A elements which is the only non-metal ?

chemistry study of the first element - hydrogen position of hydrogen in the periodic table hydrogen in periodic table trends in groups and periods

  1. Hydrogen

  2. Lithium

  3. Sodium

  4. Potassium

Show answer
Correct Option: A
Explanation:

In alkali metals hydrogen is the only non metal diatomic hydrogen gas.

The element symbol for hydrogen is:

chemistry study of the first element - hydrogen position of hydrogen in the periodic table hydrogen in periodic table trends in groups and periods

  1. K

  2. H

  3. He

  4. Hn

Show answer
Correct Option: B
Explanation:

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.