The metric prefix kilo means 1,000.
Example: A kilometer is equal to 1,000 meters.
        
             
        
        
        
Molecular mass of Mg(OH)2
= Atomic mass of Mg + 2(Atomic mass of O) + 2(Atomic mass of H)
= 24 g/mol + 2(16 g/mol) + 2(1 g/mol ) 
= 58 g/mol
Molecular mass of Fe2O3
= 2(Atomic mass of Fe) + 3(Atomic mass of O)
= 2(56 g/mol) + 3(16 g/mol) 
= 160 g/mol
 
        
                    
             
        
        
        
Answer:
v = 450 m/s
Explanation:
Given data:
Frequency = 75 Hz
Wavelength = 6 m
Velocity = ?
Solution:
Velocity is the product of frequency and wavelength.
v = f × λ
v = 75 Hz ×  6 m
Hz = s⁻¹
v = 75  s⁻¹  ×  6 m
v = 450 m/s
 
        
             
        
        
        
To add tartness / good luck and will you mark me brainliest please
        
                    
             
        
        
        
If Ka for HCN is 6. 2×10^−10 at 25 °C, then the value of Kb for cn− at 25 °C is 1.6 × 10^(-5).
<h3>What is base dissociation constant? </h3><h3 />
The base dissociation constant (Kb) is defined as the measurement of the ions which base can dissociate or dissolve in the aqueous solution. The greater the value of base dissociation constant greater will be its basicity an strength. 
The dissociation reaction of hydrogen cyanide can be given as 
HCN --- (H+) + (CN-) 
Given, 
The value of Ka for HCN is 6.2× 10^(-10) 
The correlation between base dissociation constant and acid dissociation constant is 
Kw = Ka × Kb
Kw = 10^(-14) 
Substituting values of Ka and Kw, 
Kb = 10^(-14) /{6.2×10^(-10) }
= 1.6× 10^(-5) 
Thus, the value of base dissociation constant at 25°C is 1.6 × 10^(-5).
learn more about base dissociation constant :
brainly.com/question/9234362
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