Answer:
135g Na2CO3
Explanation:
I'm going to assume you mean Molality which is mol solute/kg solvent
Molarity would be mol soute/ L solution
we know we have 155g of water which is .155 kg
essentially we have the equation:
mol/kg = 8.20
we substitute .155 in for kg and get:
mol/.155 = 8.20
Solving this gives mol = 1.271
now we must convert to grams using the molar mass
Molar mass Na2CO3 = 106G/mol
so to cancel moles we multiply:
1.271mol x 106g/mol
= 135g
Answer:
the change in the system internal energy is 20 J
Explanation:
The computation of the change in the system internal energy is as follows:
Since the volume remains constant so the work done would be zero
Now the change in the internal energy is
= Heat given to system - work done
= 20 J - 0
= 20 J
hence, the change in the system internal energy is 20 J
The same is to be considered
Answer:
1. CaO + H₂O ----> Ca(OH)₂
Compound ----- Compound
2. 2 Na + Cl₂ ----> 2 NaCl
Element ----- Element
3. 2 SO₂ + O₂ ----> 2 SO₃
Element ----- Compound