NaOH will dissociate as Na+ and OH- in the solution.
        
             
        
        
        
It's not really possible to tell longitudinal vs. transverse in this image as given. However, we can say that the waves labeled A are high-frequency (short wavelengths) while the waves labeled B are low-frequency (long wavelengths). So, this third answer choice would be correct here.
 
        
             
        
        
        
Answer: The molar mass of each gas 
Explanation:
Mole fraction is the ratio of moles of that component to the total moles of solution. Moles of solute is the ratio of given mass to the molar mass.

Suppose if there are three gases A, B and C.
a) 
b) 
c) 
moles of solute =
Thus if mass of each gas is known , we must know the molar mass of each gas to know the moles of each gas.
 
        
             
        
        
        
Answer:
60.02 g.
Explanation:
- It is clear from the balanced equation:
 
<em>Mg + 2HCl → MgCl₂ + H₂.
</em>
that 1.0  mole of Mg reacts with 2.0 moles of HCl to produce 1.0 mole of MgCl₂ and 1.0 moles of H₂.
- 20.0 g of Mg reacts with excess HCl. To calculate the no. of grams of HCl that reacted, we should calculate the no. of moles of Mg:
 
<em>no. of moles of Mg = mass/atomic mass</em> = (20.0 g)/(24.3 g/mol) = 0.823 mol.
- From the balanced equation; every 1.0 mol of Mg reacts with 2 moles of HCl.
 
∴ 0.833 mol of Mg will react with (2 x 0.833 mol = 1.646 mol) of HCl.
<em>∴ The mass of reacted HCl = no. of moles x molar mass</em> = (1.646 mol)(36.46 g/mol) = <em>60.02 g.</em>
 
        
             
        
        
        
Chromium is a fairly active metal. It does not react with water, but reacts with most acids. It combines with oxygen at room temperature to form chromium oxide (Cr 2 O 3 ). Chromium oxide forms a thin layer on the surface of the metal, protecting it from further corrosion (rusting).