Answer:
Research is constantly deepening our understanding of chemistry, and leading to new discoveries. Chemistry will help us solve many future problems, including sustainable energy and food production, managing our environment, providing safe drinking water and promoting human and environmental health.Chemistry is a big part of your everyday life. You find chemistry in daily life in foods you eat, air you breathe, soap, your emotions and literally every object you can see or touch. ... Food is made from chemicals. Many of the changes you observe in the world around you are caused by chemical reactions.By observing chemical reactions, we are able to understand and explain how the natural world works. Chemical reactions turn food into fuel for your body, make fireworks explode, cause food to change when it is cooked, make soap remove grime, and much more.
 
        
             
        
        
        
Answer:
(b) Both have the same number of valence electrons.  
Step-by-step explanation:
We find the most striking chemical similarities between two Main Group elements when they are in the same Group of the Periodic Table.
Elements in the same Group have the same number of valence electrons.
(a) is <em>wrong</em>, because elements in the same group have <em>different masses</em>.
(c) is <em>wrong,</em> because atoms with the same number of protons belong to the s<em>ame element</em>.
(d) is wrong, because elements in the same Group must be in .
<em>different Periods.</em>
 
        
             
        
        
        
Answer:
B. is often done in nature preserves
Explanation:
edge 2021
 
        
                    
             
        
        
        
Take note of the subscript written for each element in the compound. To find the total number of moles, make sure to multiply the subscript with the number of moles of compound. The answer for each is written below:
a. 3*1 = 3 moles Nitrogen; 3*3 = 9 moles Hydrogen
b. 0.25*2 = 0.5 moles Hydrogen; 0.25*1 = 0.25 moles Oxygen
c. 5*2 = 10 moles Hydrogen; 5*1 =5 moles Sulfur; 5*4 = 20 moles Oxygen
d. 0.75*1 = 0.75 moles Calcium; 0.75*1*2 = 1.5 moles Nitrogen; 0.75*3*2 = 4.5 moles Oxygen
        
             
        
        
        
Absolute zero is measured in kelvin and kelvin is -324 degree celsius witch turns most elements turn solid