<u>Answer:</u>
<em>0.264 g of
can be formed from 288 mg of
</em>
<u>Explanation:</u>
The balanced chemical equation is

The conversions are
Mass in mg
is converted to mass in g
Mass in g
is converted to moles
by dividing with molar mass
Moles
is converted to moles
by using the mole ratio of
is 9 : 6
Moles
is converted to mass
by multiplying with molar mass 
mass in mg
> mass in g
>moles
> moles
> mass 

=0.264g (Answer)
Chemical reaction, generally speaking. It's a vague definition, but it's easy to remember.
Quartz is a substance because the material has uniform properties throughout and is held together via chemical bonds.
Answer:
a number assigned to an element in chemical combination which represents the number of electrons lost (or gained, if the number is negative), by an atom of that element in the compound
Explanation:
sodium, magnesium, iron is zero.
1kg is about 2.2 pounds. So 4kg = 8.8 pounds. If that represent 19% of the total, here is the answer.
0.19*x=8.8
x=8.8/0.19
x=46.31 pounds