Question

Air Pollution Nitrogen oxide, which is present in urban air pollution, immediately converts to nitrogen dioxide as it reacts with oxygen. a. Write the balanced chemical equation for the formation of nitrogen dioxide from nitrogen oxide. b. What mole ratio would you use to convert from moles of nitrogen oxide to moles of nitrogen dioxide?

Short answer

a. The balanced chemical equation for the formation of nitrogen dioxide is: \(2NO + O_2 \rightarrow 2NO_2\) b. The mole ratio between nitrogen oxide and nitrogen dioxide is 1:1.

Step-by-step solution

Write the unbalanced chemical equation

We start by writing the unbalanced chemical equation for the reaction between nitrogen oxide (NO) and oxygen (O2) to form nitrogen dioxide (NO2). We write this as: NO + O2 → NO2

Balance the chemical equation

Next, we need to balance the chemical equation. Ensure that there are the same number of atoms of each element on both sides of the equation. We can do this by placing coefficients in front of the chemical formulas as needed. After doing so, we get the balanced chemical equation: 2NO + O2 → 2NO2 This means that 2 moles of nitrogen oxide (NO) react with 1 mole of oxygen (O2) to produce 2 moles of nitrogen dioxide (NO2).

Determine the mole ratio

Now that we have the balanced chemical equation, we can determine the mole ratio between nitrogen oxide and nitrogen dioxide. The mole ratio is the relationship between their coefficients in the balanced equation, which is: 2 moles of NO : 2 moles of NO2

Simplify the mole ratio

We can simplify the mole ratio by dividing both sides by the greatest common divisor. Dividing both sides by 2, we get: 1 mole of NO : 1 mole of NO2 The mole ratio between nitrogen oxide and nitrogen dioxide is 1:1. Answer: a. The balanced chemical equation for the formation of nitrogen dioxide is: 2NO + O2 → 2NO2 b. The mole ratio between nitrogen oxide and nitrogen dioxide is 1:1.

Key concepts

Balanced Chemical Equation

Balancing a chemical equation is crucial because it reflects the law of conservation of mass. This law states that matter cannot be created or destroyed in an isolated system. When balancing an equation, your goal is to have the same number of each type of atom on both sides of the equation.
For instance, consider the reaction between nitrogen oxide (\( \text{NO} \)) and oxygen (\( \text{O}_2 \)) to form nitrogen dioxide (\( \text{NO}_2 \)). Initially, this chemical equation is written unbalanced: \( \text{NO} + \text{O}_2 \rightarrow \text{NO}_2 \).
To balance, we find that the coefficient 2 is required in front of both \( \text{NO} \) and \( \text{NO}_2 \), yielding a balanced equation:\( 2\text{NO} + \text{O}_2 \rightarrow 2\text{NO}_2 \).
This indicates that two molecules of nitrogen oxide react with one molecule of oxygen to produce two molecules of nitrogen dioxide. By adjusting coefficients instead of changing subscripts, the chemical identities stay consistent, while mass is conserved.

Mole Ratio

The mole ratio is derived from a balanced chemical equation and plays a fundamental role in chemical calculations. It provides proportional relationships between the amounts of reactants and products involved in a chemical reaction.
This is key in stoichiometry, where chemists use mole ratios to predict how much product will form from given reactants.
Taking our reaction of \( 2\text{NO} + \text{O}_2 \rightarrow 2\text{NO}_2 \) as an example, the balanced equation gives us a mole ratio of 2 moles of \( \text{NO} \) to 2 moles of \( \text{NO}_2 \).

• Step 1: Identify coefficients from the balanced equation.
• Step 2: Write the ratio as 2 \( \text{NO} \): 2 \( \text{NO}_2 \)
• Step 3: Simplify if possible, leading to 1 \( \text{NO} \): 1 \( \text{NO}_2 \)

This 1:1 ratio tells us that one mole of nitrogen oxide will produce one mole of nitrogen dioxide. With a balanced equation, chemists easily calculate reactant volumes or product yields.

Nitrogen Oxide

Nitrogen oxide (\( \text{NO} \)) is one of several oxides of nitrogen and is of significant importance in atmospheric chemistry. It is often a product of combustion processes and plays a role in various industrial contexts.
In urban areas, nitrogen oxide is a primary component of air pollution, mainly due to vehicle emissions. As an air pollutant, NO contributes to the formation of harmful substances like nitrogen dioxide and, subsequently, photochemical smog.

• Formation: Usually produced in combustion at high temperatures (e.g., car engines).
• Impact: Contributes to acid rain and ozone layer damage.

Understanding the behavior of nitrogen oxide and its conversion into nitrogen dioxide helps manage air quality and reduce urban pollution risks.

Nitrogen Dioxide

Nitrogen dioxide (\( \text{NO}_2 \)) is a reddish-brown gas with a sharp, biting odor. It is a significant air pollutant and contributes to atmospheric processes such as photochemical smog.
NO2 is typically formed in the air through the oxidation of nitrogen oxide (\( \text{NO} \)) which reacts with oxygen molecules:
\( \text{2NO} + \text{O}_2 \rightarrow \text{2NO}_2 \)This reaction highlights NO2’s role in environmental chemistry:

• Health Effects: Can irritate the respiratory system, exacerbating asthma and reducing lung function.
• Environmental Role: A precursor to acid rain; participates in creating tropospheric ozone.

By understanding the formation and effects of nitrogen dioxide, we can target strategies to combat urban pollution and protect public health effectively.