Look at the periodic table to find the charge on atoms.
Magnesium is +2 and Nitrogen is -3. Since there are two nitrogen charge 2*-3 = -6 there needs to be 3 Mg then (3*2+ = 6+) to pair with the two nitrogen.
3 Mg(+2) + 2 N(-3) = Mg3N2
A mirror is opaque, meaning that it reflects the light and images that shine on it's reflective surface.
Molar mass CuSO4.5H2<span>O => 249.685 g/mol
Volume in liters => 100 mL / 1000 => 0.1 L
</span>
1 L ----------------- 0.05 M
0.1 L -------------- ?? ( moles of <span>copper sulfate pentahydrate )
</span>
0.1 x 0.05 / 1 => 0.005 moles
1 mole ------------- <span> 249.685 g
</span>0.005 moles ------- ( mass of <span>copper sulfate pentahydrate )
</span>
0.005 x 249.685 / 1 => 1.28425 g CuSO4.5H2<span>O
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hope this helps!
