You have to use density=mass/volume formula:
Solve for x and you get
2282.75 grams
<span>Most of earths carbon is in the atmosphere in the form of a gas?</span>
We may use the molecular formula of the compound to determine the number of oxygen atoms in one formula unit. The formula unit is:
Mg(NO₃)₂
Here, we can see that there are two nitrate ions in each mole, and each mole of nitrate ion contains three oxygen atoms. Thus, there are 6 oxygen atoms in each formula unit of magnesium nitrate.
Water, lower, and I'm not too sure for the third one... sorry.
