Galileo said that the Sun revolved around the Earth, and that the Earth was the center of the universe ! (:
Answer:
If this is an idea gas then 1mol takes up 22.4L.
So, knowing how many L you have you can figure out how many mole syou have by doing a simple equation:

Solve for y.
Then, since you know how many moles you have use the ptable https://ptable.com/#Properties to figure out the mass in grams.
NOTE: The ptable tells you that 1mol of H = 1g.....so this should be an easy calculation :) enjoy
To identify why a metal measurement was different in the experiments look for the variable that was different in the experiment and analyze how this change affected the results.
<h3>What is an experiment?</h3>
An experiment is a procedure that aims at probing or discovering something. For example, you can test if a plant grows faster/slower by using an experiment.
<h3>What causes different results in similar experiments?</h3>
The most common cause for this situation is that one of the factors or variables is slightly different. For example, if I add 50mL of water to a plant rather than 20mL of water every day this might cause different results.
Based on this, if the metal content was different you should analyze if any of the factors changed in this experiment and find out how this change affected the general results.
Note: This question is incomplete because there is limited information about the experiment; due to this, I answered it based on general knowledge.
Learn more about experiments in: brainly.com/question/13270830