Question

Write the formula of a compound of hydrogen with (a) sulfur. (b) nitrogen, which is a liquid at \(25^{\circ} \mathrm{C}\) and \(1 \mathrm{~atm}\). (c) phosphorus, which is a poisonous gas at \(25^{\circ} \mathrm{C}\) and \(1 \mathrm{~atm}\).

Short answer

Answer: The formulas of the hydrogen compounds are H2S (hydrogen sulfide) with sulfur, NH3 (ammonia) with nitrogen, and PH3 (phosphine) with phosphorus.

Step-by-step solution

(a) Hydrogen compound with sulfur

A compound of hydrogen and sulfur is hydrogen sulfide (H2S). It is a gas at room temperature and pressure. The most common compound formed by these two elements is H2S. So, the formula of the hydrogen compound with sulfur is H2S.

(b) Hydrogen compound with nitrogen that is a liquid at \(25^{\circ} \mathrm{C}\) and $1 \mathrm{~atm}\(

Among the possible hydrogen compounds with nitrogen, ammonia (NH3) is the one which appears as a liquid at \)25^{\circ} \mathrm{C}\( and 1 atm. While there are other possible hydrogen-nitrogen compounds, ammonia is the most common one that meets the given conditions. So, the formula of the hydrogen compound with nitrogen, which is a liquid at \)25^{\circ} \mathrm{C}\( and \)1\mathrm{~atm}$, is NH3.

(c) Hydrogen compound with phosphorus that is a poisonous gas at \(25^{\circ} \mathrm{C}\) and $1 \mathrm{~atm}\(

A poisonous gas formed by hydrogen and phosphorus is phosphine (PH3). This compound is less common than the other hydrogen-phosphorus compound, but it is known for its toxic nature. So, the formula of the hydrogen compound with phosphorus, which is a poisonous gas at \)25^{\circ} \mathrm{C}\( and \)1\mathrm{~atm}$, is PH3.

Key concepts

Hydrogen Sulfide

Hydrogen sulfide (H₂S) is a chemical compound that combines hydrogen and sulfur. This colorless gas is known for its distinctive rotten egg smell.
From a chemical perspective, hydrogen sulfide is a simple binary compound where two hydrogen atoms bond with one sulfur atom:

• The chemical formula for hydrogen sulfide is H₂S.
• It is important to note that hydrogen sulfide is naturally occurring in crude oil, natural gas, and hot springs.
• This compound is also produced by the breakdown of organic matter in the absence of oxygen, involving bacteria.

Despite being colorless, hydrogen sulfide is hazardous. It is highly toxic, and can be a threat to health at higher concentrations. Even at low levels, prolonged exposure can cause respiratory issues and irritation. Given its toxic nature, understanding hydrogen sulfide's properties and safety measures is crucial for working in environments where it might be present.

Ammonia

Ammonia (NH₃) is a compound composed of nitrogen and hydrogen. Unlike other compounds mentioned, ammonia is usually recognized in its gaseous state, although it can be liquefied under certain conditions.
For the exercise, ammonia is considered in its liquid form:

• The formula for ammonia is NH₃. It consists of one nitrogen atom bonded to three hydrogen atoms.
• At standard conditions, ammonia is a gas, but it can be compressed into a liquid form at room temperature.
• Ammonia is extensively used in agriculture as a fertilizer and an ingredient in chemical synthesis.

Ammonia is essential in many biological processes and industrial applications, but it can be irritating in high concentrations. It is crucial to handle it with care, observing appropriate safety measures when in liquid or gaseous form.

Phosphine

Phosphine (PH₃) is a compound where phosphorus is bonded to hydrogen. It is a noxious gas at room temperature and pressures, notably known for being highly poisonous.
Phosphine's composition and properties include:

• Its chemical formula is PH₃, indicating a single phosphorus atom bonded to three hydrogen atoms.
• This compound takes a gaseous form and is infamous for its toxicity and dangerous nature.
• Phosphine arises primarily during industrial processes and can be a byproduct during the handling of phosphorous-containing substances.

Safety is paramount when dealing with phosphine, as even small concentrations can be lethal. It is important to use adequate protective gear and ventilation systems when working in environments where phosphine might be present.