Solution:
Molality:-It is a measure of the concentration of a solute in a solution in terms of amount of substance in a specified amount of mass of the solvent
Therefore,  
Molality = moles solute / kg solvent  
Therefore kg solvent = moles solute / molality  
moles solute = mass / molar mass  
= 25.31 g / 101.1 g/mole  
= 0.2503 mole
kg solvent = 0.2503 mole / 0.1982 m  
= 1.263 kg  
= 1263 g
This is the required answer.
 
        
                    
             
        
        
        
Well to put simple. Isotopes have a different relative amount of neutrons . the more neutrons the more it weighs BUT it still is the same element
        
             
        
        
        
Answer: 1 mol of  will be produced from this reaction.
 will be produced from this reaction.
Explanation: Reaction follows,

As seen from the balanced chemical equation above, we get
For every 3 moles of Aluminium and 3 moles of  , 1 mole of
, 1 mole of  is formed.
 is formed.
For every 3 moles of Aluminium and 3 moles of  , 1 mole of
, 1 mole of  is formed.
 is formed.
For every 3 moles of Aluminium and 3 moles of  , 3 moles of
, 3 moles of  is formed.
 is formed.
For every 3 moles of Aluminium and 3 moles of  , 6 moles of
, 6 moles of  is formed.
 is formed.
 
        
                    
             
        
        
        
Answer:
i am pretty sure it is compound
 
        
             
        
        
        
<u>Q</u><u>U</u><u>E</u><u>S</u><u>T</u><u>I</u><u>O</u><u>N</u><u> </u><u>:</u>
- highest energy level for lithium
<u>A</u><u>N</u><u>S</u><u>W</u><u>E</u><u>R</u><u> </u><u>:</u>
- There are 2 electrons on the first energy level and 1 electron on the second. Explain that the first energy level can only have 2 electrons so the next electron in lithium is on the next (second) level. Explain that neon has 10 protons and 10 electrons.