Answer:
3.01×10²³ atoms of calcium
Explanation:
number of moles = number of atoms/Avogadro's constant
n = N/NA
N = n×NA = 0.500 mol×6.02×10²³ mol^-1 
N = 3.01×10²³ atoms of calcium
 
        
             
        
        
        
Answer:
b
Explanation:
I used my passion and skill for learning to do a quick google search :P
 
        
                    
             
        
        
        
And the answer is False,it does not have the same number with particles as the one mole of hydrogen.
        
                    
             
        
        
        
Answer:
54 g
Explanation:
1 mole of water = H2O
mass of 1 mole of H2O= mass of h2 + mass of o
= 2× mass of h +mass of o
= 2×1+16 =18 g
1 mole of water = 18g
3moles of water = 18×3g= 54g
 
        
             
        
        
        
Given the solubility of strontium arsenate is 0.0480 g/l . we have to convert it into mol/L by dividing it over molar mass (540.7 g/mol)
Molar solubility = 0.0480 / 540.7 = 8.9 x 10⁻⁵ mol/L
Dissociation equation:
Sr₃(AsO₄)₂(s) → 3 Sr²⁺(aq) + 2 AsO₄³⁻(aq)
                             3 s                   2 s
Ksp = [Sr²⁺]³ [AsO₄³⁻]²
       = (3s)³ (2s)²
       = 108 s⁵
Ksp = 108 (8.9 x 10⁻⁵) = 5.95 x 10⁻¹⁹