<u>Al2(SO4)3</u>
<u>Option: E</u>
<u>Explanation:</u>
The freezing point lowering of a solution depends on the number of ions and molecules that dissolve in water solution. So when there are more number of molecules, the freezing point will also be reduced more.
Now let us look at Al2(SO4)3. Here, it produces a total of 5 molecules. i.e (2 Al(3+) and 3 SO4(2-)). If we take the other choices from first:
MgBr2 - It produces a total of 3 molecules. (1 Mg(2+) and 2 Br(-))
HOCH2CH3 - This produces 1 molecule as it remains the same as HOCH2CH3 because it is covalent and does not dissociate in water.
NaNO3 - This produces 2 molecules. (1 Na(1+) and 1 NO3(-))
C6H12O6 - This also produces 1 molecule same as HOCH2CH3 because it is also covalent and does not dissociate in water.
Na3PO4 - This produces a total of 4 molecules. (3 Na(+) and 1 PO4(3-))
Thus, from the above analysis, it shows that Al2(SO4)3 has more molecules compared to others. When there are more molecules, the freezing point is also lower.
Answer:
Fe(iii)2O3 + 3CO ===> 2Fe + 3CO2
Explanation:
Fe(iii)2O3 + CO ===> Fe + CO2
The best thing to do is start with the Oxygens. They are the most complicated.
Fe(iii)2O3 + 3 CO ===> Fe + 3 CO2
Unfortunately this equation is a bit of by guess and by gosh. You need to balance the oxygens so that the total is an even number. That's because the right hand side is always going to be even. [The 2 on CO2 will make anything in front of it even).
So there are 6 oxygens on the left and 6 on the right. The carbons by accident are balanced with this maneuver. So all that is left is the irons.
Fe(iii)2O3 + 3CO ===> 2Fe + 3CO2
This equation is a bit nasty, but in higher chemistry courses, you will learn how to make it a whole lot simpler. For now you are just going to have to put up with the nastiness of the question and guess.
Answer:
They are a base and an acid, so they neutralize each other.
Explanation:
Sodium hydroxide is a strong base. Hydrochloric acid is a strong acid.
They react with (neutralize) each other to form a salt (sodium chloride) and water.
NaOH + HCl ⟶ NaCl + H₂O