Explanation:
The given data for case (1) is as follows.
   h = 20 cm = 0.2 m
Assuming that a rectangular slab is placed above the pipe and we will calculate the heat transfer as follows.
               Q =  
 
   where,    A = area 
                   L = length
                   k = thermal conductivity = 0.8 W/m
               = change in temperature.
 = change in temperature.
Therefore, putting the given values into the above formula as follows.
             Q =  
 
                 =  
 
                 = 168 W
For case (2), h = 180 cm = 1.8 m
Therefore, heat lost will be calculated as follows.
                        Q =  
 
                            =  
 
                            = 18.67 W
Thus, we can conclude that 18.67 W heat lost if the pipe was buried at a depth of 180 cm.
 
        
             
        
        
        
Answer:
C.) 2
Explanation:
The pH equation is:
pH = -log[H⁺]
In this equation, [H⁺] is the molarity of the acid. In this case, the acid is HCl. Molarity can be found using the equation:
Molarity (M) = moles / volume (L)
Since you were given moles and volume, you can find the molarity of HCl.
Molarity = moles / volume
Molarity = 0.01 moles / 1.00 L
Molarity = 0.01 M
Now, you can plug the molarity of the acid into the pH equation.
pH = -log[H⁺]
pH = -log[0.01]
pH = 2
 
        
             
        
        
        
IT DIDN'T ROLL ROOSTERS CAN LAY EGGSS AHHH
        
                    
             
        
        
        
 2.23 moles of propane react when 294 g of CO₂ is formed .
<h3>What is moles ?</h3>
Moles is a unit which is equal to the molar mass of an element.
A reaction is given
C₃H₈ +50₂ → 3CO₂ + 4H₂O
Grams of CO₂ formed = 294 gm 
In moles = 294 /44 = 6.68 moles.
Let x be the moles of C₃H₈ is x 
Mole ratio of CO₂ to C₃H₈ = 3 : 1
so
6.68 /x = 3/1
x = 6.68 /3 = 2.23 moles
Therefore 2.23 moles of propane react when 294 g of CO₂ is formed .
To know more about Moles
brainly.com/question/26416088
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Answer:
Atomic mass of an element is not a whole number because It contains isotopes. For example, chlorine has two isotopes 1735Cl and 1737Cl with natural abundances in the approximate ratio of 3:1. Hence, the average atomic mass of chlorine is approximately 35.5 g/mol.
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