Answer:
B. Conclusions are based on observations
Explanation:
 
        
             
        
        
        
The reaction: 2H2(g) + O2(g) → 2H2O(g), can be interpreted as: a. 2 moles of hydrogen gas reacts with 1 mole of oxygen gas to produce 2 moles of water.
 
        
                    
             
        
        
        
Acid-base indicator changes color based on pH.
drop some in a solution n watch the color changes. different indicators show different colors at different pH. they usually have standard colors for comparison.
        
                    
             
        
        
        
Wood is a Heterogeneous Mixture.
Hope this helps
        
             
        
        
        
Explanation:
1: fluorine to form lithium fluoride
2:bcos covalent bond exists btw two non metals
3: bcos it is d combination of two or more elements nd elements r substances
4: for sbustances we hv flame test nd splint test
ionic compounds are held by strong electrostatic forces of attraction