The 2 in front of 
in 
is <u>Coefficient.</u>
_____________________________
The 
after 
in the same equation is <u>sub </u><u>script</u><u>.</u>
_____________________________
There are two atoms of in 
_____________________________
Answer:
46.40 g.
Explanation:
- It is a stichiometric problem.
- The balanced equation of the reaction: 4K + O₂ → 2K₂O.
- It is clear that 4.0 moles of K reacts with 1.0 mole of oxygen produces 2.0 moles of K₂O.
- We should convert the mass of K (38.5 g) into moles using the relation:
<em>n = mass / molar mass,</em>
n = (38.5 g) / (39.098 g/mol) = 0.985 mole.
<em>Using cross multiplication:</em>
4.0 moles of K produces → 2.0 moles of K₂O, from the stichiometry.
0.985 mole of K produces → ??? moles of K₂O.
∴ The number of moles of K₂O produced = (0.985 mole) (2.0 mole) / (4.0 mole) = 0.4925 mole ≅ 0.5 mole.
- Now, we can get the mass of K₂O:
∴ mass = n x molar mass = (0.5 mole) (94.2 g/mol) = 46.40 g.
Answer:
60 V
Explanation:
From;
Vs/Vp = Ns/Np
Where;
Vs = voltage in the secondary coil = 6V
Vp = voltage in the primary coil= ??
Ns = number of turns in the secondary coil = 9
Np= number of turns in the primary coil = 90
6/Vp = 9/90
Vp= 90 * 6/9
Vp= 60 V
