1.B
6.D 
D because t<span>he mass of one mole (molar mass) of helium gas is </span>4.002602 g/mol. 4.002602 * 5=20.01309. Rounded equals 20. So, the answer is D.20 g.
        
             
        
        
        
There’s no pic for me to awnser your question
        
                    
             
        
        
        
Answer:
no it's not solid rather it's an aqueous 
Explanation:
B/c Barium hydroxide is used in analytical chemistry for the titration of weak acids, particularly organic acids. Its clear aqueous solution is guaranteed to be free of carbonate, unlike those of sodium hydroxide and potassium hydroxide, as barium carbonate is insoluble in water.
 
        
             
        
        
        
Answer:
The atomic number on the Periodic Table identifies the number of protons in any atom of that element. Copper, atomic number 29, has 29 protons. Finding the atomic number of an element reveals the number of protons.
To find the number of neutrons in the atom, subtract the atomic number from the atomic mass.
 
        
             
        
        
        
Answer:
are a gas at very low volumes, when gas particles are very close together
a gas at very low temperatures, when gas particles have very little kinetic energy
a gas with highly polar molecules that have very strong intermolecular forces
Explanation: