Hydrogen Gas H or H2

[Tess_Fleser_1D]

In part a of problem H7 (Write a balanced chemical equation for each of the following reactions. (a) Calcium metal reacts with water to produce hydrogen gas and aqueous calcium hydroxide.), should we assume hydrogen gas is H2 or H?

[Chem_Mod]

Yes, Hydrogen gas always refers to its diatomic form (H2).

[Vy Le 1G]

Hi Tess! I always assume that "hydrogen gas" refers to its diatomic form H2 and "hydrogen" alone or "hydrogen atom" refers to the element H. Hope it helps! This is also similar when the book talks about oxygen versus oxygen gas.

[Somin Lee]

yes When it says hydrogen gas in the question you should interpret it as H2 because Hydrogen can only exist as gas in diatomic form. Same thing for other diatomic elements (F, O, Br, N, I, Cl)

[Hannah Carsey 1B]

When writing hydrogen in a chemical reaction or in its naturally occurring state (H2 (g)), you write it as a diatomic molecule as it is one of the 7 diatomic molecule. The 7 diatomic molecules are (N2, H2, F2, O2, I2, Cl2, Br2) and these 7 diatomic molecules are always written as such when they are isolated / not a part of a covalent molecule or ionic compound.

[Chris Oh 2I]

People already answered this but a fun mnemonic to remember those diatomic molecules is Dr. HOFBrINCl (Hydrogen, Oxygen, Fluorine, Bromine, Iodine, and Chlorine)!

[Amy Shimizu 1J]

Hydrogen gas is a diatomic molecule, meaning it will always be in the form of H2!

[Sidharth Paparaju 3B]

Hydrogen gas is going to be H2 since its diatomic--meaning that in nature hydrogen is always found as H2.

[Leah Wildmann 1F]

Hydrogen gas will always by H2. H should be used for "hydrogen atom" or just "hydrogen".

[Michelle Argueta 1E]

Yes. If hydrogen is being referred to as 'hydrogen gas' it should be written as a diatomic molecule: H2. Similarly, other diatomic molecules such as Nitrogen, Flourine, Oxygen, Iodine, Chlorine, and Bromine, will have a subscript of '2' when they are in gas states. A way to remember these diatomic molecules is using the mnemonic of 'Have No Fear Of Ice Cold Beer.'

[Kaitlyn Bateman 1L]

Hi! Many gases appear in nature in a diatomic form, like O2 or H2. So in this equation (like combustion equations with O2) it would be H2.

[Nova Akhavan 2F]

Hydrogen is a diatomic molecule so "Hydrogen Gas" should always be written as H2 unless a problem indicates otherwise or specifically mentions a "hydrogen atom."

[Cassidy Chiong 2J]

Hydrogen gas will always be H2 since it is a diatomic molecule.

[Ivan_Tang_2G]

Hydrogen Gas should be in the form H2 given that it is gas form!

[Rainy Liu Ruoshui_2K]

As an element, hydrogen exists in hydrogen gas H2 in natural forms. So in this problem, it's asking for H2.

H is usually referred to as an atom.

[Aryan Gajjar 3D]

Hydrogen gas should always be written as H2 (g) and not as H because it is a diatomic molecule.

[Eric Sun 2G]

Hydrogen is diatomic, meaning that when found in nature, Hydrogen will always be in the form of H2 instead of just H. Some other diatomic molecules also include Br,I,N,Cl,O, and F.

[Ryan Lafferty 1L]

Hydrogen gas should be written as H2, as it is a diatomic molecule. H should be used to represent an atom of the element Hydrogen. Hopefully this helps!

[Matthew Li 1B]

hydrogen gas exist as H2

[Jillian Sarquiz- 2B]

Hydrogen gas should be written as H2 every time!

[Nithya Madhu 2L]

Hydrogen gas should be H2. This is because hydrogen as a gas exists only in its diatomic form of H2. The other diatomic molecules are N2, F2, O2, I2, Cl2, Br2

[Molly Smith 1J]

Hydrogen gas is always H2. This is because each hydrogen atom has 1 electron, and the bottom electron orbital holds two electrons. Therefore, H atoms are likely to form a covalent bond and share electrons, giving them both two electrons and filling the orbital. Hence, in hydrogen gas, it is H2.

Hope this helps!

[Nicole Ton 3C]

Hydrogen gas always comes as H2. A H by itself would just be the atomic version. Hydrogen is an example of a diatomic element, which means that it forms molecules of two of its atoms, in this case H2. So, whenever a question asks for hydrogen gas, it would be H2 rather than just H.

[Joanna Zhao 1J]

I'm going to repeat what everyone else has said: correct, hydrogen gas is diatomic (H2). For future reference, other elements that are diatomic in gas form are nitrogen (N2), oxygen (O2), fluorine (F2), and chlorine (Cl2) and bromine and iodine are commonly diatomic as well in chemistry problems (but I mentioned them separately because Br2 and I2 are liquid and solid, respectively, at room temperature). I'd say that it's worth memorizing (or at least familiarizing yourself with) these commonly diatomic elements.

[Lindsey Walter 3E]

Always H2! Hydrogen is diatomic (meaning that unless specified, hydrogen gas will always be H2). Other diatomics include: Nitrogen, Oxygen, Fluorine, Iodine, Chlorine, and Bromine.

[Caitlyn Lo 2F]

Yes hydrogen gas is always present as H2 because it is a diatomic element.

[Grace_Wu]

When referring to hydrogen gas, it is always H2, while hydrogen atom is H only.

[Do Yeun Park]

Hydrogen gas is always H2 because it's a diatomic element. Along with Hydroge, Br, I, N, Cl, O, and F's gas form is Br2, I2, N2, Cl2,O2, and F2, respectively.

[Simone Byun 1F]

Hydrogen gas will always be H2, as H alone is just an atom. Many halogens are also like this (Cl, Br, I, etc).

[205705413]

Hydrogen gas is always H2 because it is a diatomic atom.

[Sean Sanders 1E]

Hydrogen gas always refers to its natural state, H2, because hydrogen is one of the seven diatomic elements.

[Lyndon Cope 2D]

Typically in problems like this H2 would be correct because it refers to hydrogen gas. Hydrogen is a diatomic element which means found in its natural gaseous state it forms as H2. Other diatomic elements include Oxygen, Nitrogen, Chlorine, Bromine, and Fluorine.