Answer:
A. 4.
Explanation:
<em>no. of moles (n) = mass/molar mass.</em>
mass = 64.0 g, molar mass = 16.0 g/mol.
∴ no. of moles (n) = mass/molar mass = (64.0 g)/(16.0 g/mol) = 4 mol.
 
        
             
        
        
        
Answer:
Save the *minerals* used to extract metals.
 
        
             
        
        
        
The mass of carbon contained in 2.25 g of potassium carbonate, K₂CO₃ is 0.196 g.
<h3>
Molecular mass of potassium carbonate</h3>
The molecular mass of potassium carbonate, K₂CO₃ is calculated as follows;
M = K₂CO₃
M = (39 x 2) + (12) + (16 x 3)
M = 138 g
mass of carbon in potassium carbonate, K₂CO₃ is = 12 g
The mass of carbon contained in 2.25 g of potassium carbonate, K₂CO₃ is calculated as follows;
138 g ------------ 12 g of carbon
2.25 g ------------ ? 
= (2.25 x 12) / 138
= 0.196 g
Thus, the mass of carbon contained in 2.25 g of potassium carbonate, K₂CO₃ is 0.196 g.
Learn more about potassium carbonate here: brainly.com/question/27514966
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