Final answer:
The new pressure of the ideal gas is approximately 2.0 atm.
Step-by-step explanation:
To find the new pressure of the ideal gas, we can use the combined gas law, which states that P₁V₁/T₁ = P₂V₂/T₂. In this case, the initial pressure (P₁) is 1 atmosphere, the initial volume (V₁) is 1 m³, the initial temperature (T₁) is 300 K, the final temperature (T₂) is 450 K, and the final volume (V₂) is 0.75 m³. Plugging in these values, we can solve for the final pressure (P₂).
Substituting the known values:
P₁V₁/T₁ = P₂V₂/T₂
1 * 1 / 300 = P₂ * 0.75 / 450
0.00333 ≈ P₂/600
P₂ ≈ 0.00333 * 600
P₂ ≈ 2.0 atm
Therefore, the new pressure of the ideal gas is approximately 2.0 atm.