Answer:
Controlling the environment is the most key procedures for getting good results.
Explanation:
The control environment for an experiment is the essential part for getting good results. In control environment, there is no or less chances of disruption
from the external environment which can cause the results of the data more acceptable. So the scientists prefers laboratory for performing experiment as compared to outer environment. So in my opinion for getting better results, the control environment is the most necessary experimental procedure.
Group 8 elements. They are unreactive and stable
The new pressure : P₂ = 1038.39 mmHg
<h3>Further explanation</h3>
Given
1.5 L container at STP
Heated to 100 °C
Required
The new pressure
Solution
Conditions at T 0 ° C and P 1 atm are stated by STP (Standard Temperature and Pressure).
So P₁ = 1 atm = 760 mmHg
T₁ = 273 K
T₂ = 100 °C+273 = 373 K
Gay Lussac's Law
When the volume is not changed, the gas pressure is proportional to its absolute temperature

Input the value :
P₂=(P₁.T₂)/T₁
P₂=(760 x 373)/273
P₂ = 1038.39 mmHg
Answer:
The substance is a mixture because it left a white powder in the beaker when boiled.
Explanation:
The answer that h are looking for is c