Answer:
1.) 28.0 grams of oxygen28 grams (1 mole/16 grams per mole)=1.75 moles oxygen2.)5.0 moles of Iron5 moles(55.845 grams/1 mole)=279.225 grams Iron3.) 452 grams Argon452 grams(1 mole/39.948 grams)=11.315 moles Argon4.) 16.5 moles Hydrogen16.5 moles(1.01 grams/1 mole)=16.665 grams Hydrogen
Explanation:

- <em>Expansion </em><em>of </em><em>particles</em><em> </em><em>of</em><em> </em><em>substances.</em><em> </em>
- <em>Increase</em><em> </em><em>in </em><em>temperature</em><em>.</em>
- <em>Change</em><em> </em><em>in </em><em>state</em><em>.</em>
- <em>Change</em><em> </em><em>in </em><em>physical</em><em> </em><em>property</em>
- <em>It </em><em>may </em><em>bring</em><em> </em><em>out </em><em>chemical</em><em> </em><em>changes</em><em>.</em>
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Answer:
Ionic
Explanation: Ionic compounds tend to be hard and brittle while covalent compounds tend to be softer and more flexible.
Hope this helped!
Answer:
a molecule with two of the same element
Explanation: