Answer: 1.65
Explanation:
For a 0.0224M HCl solution the concentration of the hydrogen ions, 
[H+] = is 0.0224 mol/L (i.e. 0.0224 M)
pH = −log[H+]
Substituting H+ = 0.0224 into the equation 
pH = - log[0.0224]
pH = 1.649
pH = 1.65
 
        
             
        
        
        
 Microwaves are defined as electromagnetic radiations with a frequency ranging between 300 MHz to 300 GHz while the wavelength ranges from 1 mm to around 30 cm. The microwave radiation is commonly referred to as microwaves. They fall between the infrared radiation and radio waves in the electromagnetic spectrum. radio waves in the electromagnetic spectrum.
 
        
             
        
        
        
A neutral atom that loses an electron becomes a positive ion. ... An atom that gains or loses an electron becomes an ion. If it gains a negative electron, it becomes a negative ion. If it loses an electron it becomes a positive ion
        
                    
             
        
        
        
3Si + 2N2 --> Si3N4 (as given) 
n(Si) = m/MM = 38.25/28.085 = 1.3619 mol
n(N2) = 14.33/2*14.007 = 0.5115 mol
Therefore, N2 is limiting and Si is in excess 
The molar ratio of 2N2:Si3N4 is 2:1 
So, 0.0575 mol of silicon nitride is formed (dividing 0.5115 by 2) 
m of silicon nitride= n*mm = 0.0575*140.283 = 8.06627... g 
= 8.066g (4 significant figures) 
(hopefully it is right, but double check in case i did something wrong) :)