Answer:
The group 18 elements are helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn). These elements are non-reactive and are called noble gases as they have their outermost orbit complete. Due to stable electronic configuration they hardly react with other elements.The name comes from the fact that these elements are virtually unreactive towards other elements or compounds.The group 18 elements are called noble or inert gases. As the name suggests these are inert because chemically they are very less reactive or not at all reactive.The full valence electron shells of these atoms make the noble gases extremely 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
Explanation:
I
have not yet learnt chemistry so sorry
The alloy has a density of 21.186g/cc. So for a kilogram or 1000 grams/21.186 g/cc= 45.7 cc. So the answer is 45.7 cc of the allow to make up a kilogram which shows that the density of the allow can be used to calculate the volume of a larger mass ie the kilogram.