Answer:
help with problem 4
Explanation:
4. protons are equal to atomic numbers. neutrons are atomic mass minus atomic number. electrons are equal to protons. 
5. I don't know, sorry.
 
        
             
        
        
        
2) mg donates two protons to O.
        
                    
             
        
        
        
Answer:
K2SO4(aq) + Ba(NO3)2(aq)
Explanation:
K2SO4(aq) + Ba(NO3)2(aq)= 2KNO3(aq) + BaSO4(s)
The reaction produces BaSO4 
Which precipitates as the insoluble product and Soluble KNO3 solution
 
        
             
        
        
        
<h2>Answer </h2>
Matter 
<u>Explanation </u>
A matter has distinct properties and composition that never vary. The matter is anything which possesses mass and occupies space. The matter has different characteristics and a distribution that does not change from unit to unit. Materials which cannot be disintegrated into simpler materials. Each is made of only one kind of atom in subatomic level. For example, a chair, table, and similar everything that has mass and occupies space is matter.
 
        
        
        
A quantity of property that must be transferred to body to the physical system to perform work