1) When do you know if elements such as oxygen and hydrogen are in double bonds?
for example when balancing an equation, how would you figure out if O is double bonded or not? Also, which elements come in more than one bond?

2) What are formula units, how and where are they used?

3) Where do you use sig figs ?

4) How do you calculate volume, is it the same as calculating molar mass, moles, and particles?

5) How do you firgure out what state an element is in? Especially when writting equations ?

6) How would you balance this equation and create the second half of this equation:
Phosphoric Acid is produced at a fertilizer plant:
H2SO4(aq)  +   Ca(PO4)2  -->

7) How would you write a balanced equation for:
Iron(III)nitrate is reacted with sodium chromate to produce iron(III)chromate and sodium nitrate?

How do you find out if a compound is molecular or ionic?

Thanks alot, any help is appreciated !

1) When do you know if elements such as oxygen and hydrogen are in double bonds?
for example when balancing an equation, how would you figure out if O is double bonded or not? Also, which elements come in more than one bond?


H can never be doubly bonded .
O is doubly bonded if it is bonded to one atom only.Like O=C=O ,H-O-H ,

2) What are formula units, how and where are they used?
Ionic compounds are represented by formula units like NaCl, KCl

3) Where do you use sig figs ?
In scientific calculations to minimize errors .

Alright, thanks alot for all your time and help !