Answer: Its average atomic mass is 114.9 amu
Explanation:
Mass of isotope 1 = 113 amu
% abundance of isotope 1 = 5% = 
Mass of isotope 2 = 115 amu
% abundance of isotope 2 = 95% = 
Formula used for average atomic mass of an element :

![A=\sum[(113\times 0.05)+(115\times 0.95)]](https://tex.z-dn.net/?f=A%3D%5Csum%5B%28113%5Ctimes%200.05%29%2B%28115%5Ctimes%200.95%29%5D)

Thus its average atomic mass is 114.9 amu
 
        
             
        
        
        
Answer:
D.
Explanation:
Although all of these answers are similar, it seems that all three are the answer. I am sorry if the answer ends up being B but I'm pretty sure the answer is D. Charles Darwin's evolution theory "evolved", get it, from the natural selection theory. The theory is described as "the process whereby organisms better adapted to their environment tend to survive and produce more offspring." However, some factors that effect natural selection are competition, selection and variation. I believe all three fit the answer and therefore I believe answer D is correct.
 
        
                    
             
        
        
        
Answer:
A.
A chemical reaction was producing a new substance.
Explanation:
Equation of the reaction
NaOH + HCl --> NaCl + H2O 
Heat of neutralization is the amount of heat evolved when one mole of acid reacts with one mole of an alkaline to form one mole of water. 
When a neutralisation reaction is carried out, there is an exothermic change; energy released into the surroundings therefore since heat is given out which is what is felt. 
 
        
             
        
        
        
Answer:
3.6*10^7
Explanation:
I hope this helped you... Have a nice day.. UWU