Answer:
N2H4 + 2H2O2 ---->N2 + 4H2O
Explanation:
N=2 N=2
H=6 ->8 H=2 ->8
O=2 -> 4 O=1 -> 4
Add coefficients to hydrogen peroxide on the left and water on the right, so that there is an equal number of hydrogens and oxygens.
Explanation:
Bohr built on Nicholson's idea by adopting the requirement that the angular momentum can have only certain discrete values related to Planck's constant. However Bohr's atom has many orbits for the electrons.
Don't understand the text, but water always freezes at 0°C as long as its water.
The mass of MgCl₂ produced is 5.685 grams.
<h3>What is mass?</h3>
Mass is the quantity of matter of a physical body.
The reaction is
Mg + 2HCl → MgCl₂ + H₂
2 mole of HCl
(2 × 36.458) = 72.8 g
1 moles of MgCl₂
(1 × 95.21 g) = 95.21 g
1 g Mg will produce = 
4.67 mol Mg will produce

Thus, the mass of MgCl₂ produced is 5.685 grams.
Learn more about mass
brainly.com/question/19694949
#SPJ4
2Mn⁺⁴O2 + 2K2CO3 + O2 → 2KMn⁺⁷O4 + 2CO2
Mn⁺⁴ - 3e⁻ = Mn⁺⁷