<span>The strong bonds give graphite high boiling and melting points, while the weak bonds make graphite soft and flexible.</span>
        
                    
             
        
        
        
Answer: <u><em>True</em></u>
Explanation:
<u><em>Q. 10g of white powder reacts with 10g of clear liquid. The reaction bubbles and changes color producing a black liquid that has a mass of 13g. What can be ...</em></u>
 
        
             
        
        
        
Answer:
The correct answer is option B.
Explanation:

Moles of  = 40 mol
 = 40 mol
Moles of NaOH = 48 mol
According to reaction, 3 moles of NaOH reacts with 2 moles 
Then ,48 moles of NaOH will reacts with:
 of
 of 
Then ,40 moles of  will reacts with:
 will reacts with:
 of NaOH
 of NaOH
As we can see that 48 moles of sodium will completey react with 32 moles of nitrogen tribromide.
Moles left after reaction = 40 mol - 32 mol = 8 mol
Hence, the  is an excessive reagent.
 is an excessive reagent.
 
        
                    
             
        
        
        
Answer:
pH = 12.80
[H3O+] = 1.58 * 10^-13 M
[OH-] = 0.063 M
Explanation:
Step 1: Data given
pOH = 1.20 
Temperature = 25.0 °C
Step 2: Calulate pH
pH + pOH = 14
pH = 14 - pOH
pH = 14 - 1.20 = 12.80
Step 3: Calculate hydronium ion concentration 
pH = -log[H+] = -log[H3O+]
12.80 = -log[H3O+]
10^-12.80 = [H3O+] = 1.58 * 10^-13 M
Step 4: Calculate the hydroxide ion concentration
pOH = 1.20 = -log [OH-]
10^-1.20 = [OH-] = 0.063M
Step 5: Control [H3O+] and [OH-]
[H3O+]*[OH-] = 1* 10^-14 
1.58 *10^-13 * 0.063 = 1* 10^-14