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.
 
        
             
        
        
        
Doping Se (group VI elements) with P(group V)elements would produce a P-TYPE semiconductor with HIGHER conductivity compared to pure Se
the reason is P dopant will introduce holes in the Se as P has lesser valence electron
        
             
        
        
        
<u>Solar Energy & Wind Power.</u>
One of the main thing about renewable energy, it will never run out, and it saves you money. 
 
        
             
        
        
        
Answer:
Here:
Explanation:
To familiarize students with experimental apparatus, the scientific method, and methods of data analysis so that they will have some idea of the inductive process by which the ideas were originated. To teach how to make careful experimental observations and how to think about and draw conclusions from such data.