Answer
given,
change in enthalpy = 51 kJ/mole
change in activation energy = 109 kJ/mole
when a reaction is catalysed change in enthalpy between the product and the reactant does not change it remain constant.
where as activation energy of the product and the reactant decreases.
example:
ΔH = 51 kJ/mole
E_a= 83 kJ/mole
here activation energy decrease whereas change in enthalpy remains same.
 
        
             
        
        
        
Igneous rocks are conglomerates, predominantly composed of rounded
gravel
Explanation:
The statement that igneous rocks are conglomerate predominantly composed of rounded gravel is not correct. Igneous rocks are rocks formed from magma that cools and solidifies. 
- Conglomerates are sedimentary rocks that are made of rounded clasts in a matrix. 
- They differ from igneous rocks that crystallize from molten magma. 
- Sedimentary rocks are usually derived from the process of weathering, erosion, transportation and deposition on the earth surface. 
- Igneous rocks forms from crystallized magma which can be on the surface or deep within the crust. 
Learn more: 
Sedimentary rocks brainly.com/question/2740663
#learnwithBrainly
 
        
                    
             
        
        
        
Answer:
A stellar collision.
Explanation:
A stellar collision is the coming together of two stars caused by stellar dynamics within a star cluster, or by the orbital decay of a binary star due to stellar mass loss or gravitational radiation, or by other mechanisms not yet well understood.
 
        
                    
             
        
        
        
Answer:
(a)  
 
(b) 
Explanation:
Part (a)
The total length of copper cord L=86.3 m
The cross sectional area A=1.71×10⁻⁶m²
The resistivity of copper p=1.72×10⁻⁸Ω
Thus the resistance of extension cord is

Part (b)
The resistance of trimmer Rt=17.9 ohms
 When voltage of 120V is applied then the current I is passing through series circuit is

Thus the voltage across the trimmer is:
 
 
        
             
        
        
        
Answer:
D: Increase the distance between the objects.
E: Decrease the mass of one of the objects.