The density of Argon will be highest at:

Options

A. STP
B. `0^0C` , 2atm
C. `273^0C` , 1atm
D. `273^0C` , 2atm

Explanation

To determine the conditions under which the density of Argon will be highest, we can use the Ideal Gas Law, which is expressed as:

\[ PV = nRT \]

Where:
- \( P \) = pressure
- \( V \) = volume
- \( n \) = number of moles
- \( R \) = universal gas constant
- \( T \) = temperature in Kelvin

### Step 1: Rearranging the Ideal Gas Law
We can express the number of moles \( n \) in terms of density \( D \):
\[ n = \frac{m}{M} \]
Where \( m \) is the mass and \( M \) is the molar mass.

Substituting this into the Ideal Gas Law gives:
\[ PV = \frac{m}{M}RT \]

### Step 2: Expressing Density
We know that density \( D \) is defined as:
\[ D = \frac{m}{V} \]

From the rearranged Ideal Gas Law, we can express density in terms of pressure, molar mass, and temperature:
\[ D = \frac{PM}{RT} \]

### Step 3: Analyzing the Equation
From the equation \( D = \frac{PM}{RT} \):
- Density \( D \) is directly proportional to pressure \( P \).
- Density \( D \) is inversely proportional to temperature \( T \).

### Step 4: Conditions for Maximum Density
To maximize the density of Argon:
- We need to maximize pressure \( P \).
- We need to minimize temperature \( T \).

### Step 5: Conclusion
The highest density of Argon will occur at conditions of high pressure and low temperature. The standard temperature and pressure (STP) conditions are typically 0°C (273 K) and 1 atm pressure. Therefore, the density of Argon will be highest at STP.

### Final Answer
The density of Argon will be highest at STP (Standard Temperature and Pressure).

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