2SO₂ + O₂ = 2SO₃
n(O₂)=1 mol
n(SO₂)=2n(O₂)
n(SO₂)=2 mol
Explanation:
Given elements:
F, Sr, P, Ca, O, Br, Rb, Sb, Li, S
Elements with the same chemical reactivity will belong to the same group on the periodic table. This implies that elements in the same column will have the same reactivity;
Li and Rb are both alkali metals in group 1
Ca and Sr are both alkali earth metals in group 2
F and Br are halogens in group 7
O and S are group 6 elements
P and Sb are both in group 5 on the periodic table
So these groupings show elements with the same chemical properties.
Answer:
Option A.
2Na + 2H2O —> 2NaOH + H2
Explanation:
To know which option is correct, we shall do a head count of the number of atoms present on both side to see which of them is balanced. This is illustrated below below:
For Option A:
2Na + 2H2O —> 2NaOH + H2
Reactant >>>>>>> Product
2 Na >>>>>>>>>>> 2 Na
4 H >>>>>>>>>>>> 4 H
2 O >>>>>>>>>>>> 2 O
Thus, the above equation is balanced.
For Option B:
2Na + 2H2O —> NaOH + H2
Reactant >>>>>>> Product
2 Na >>>>>>>>>>> 1 Na
4 H >>>>>>>>>>>> 3 H
2 O >>>>>>>>>>>> 1 O
Thus, the above equation is not balanced.
For Option C:
2Na + H2O —> 2NaOH + H2
Reactant >>>>>>> Product
2 Na >>>>>>>>>>> 2 Na
2 H >>>>>>>>>>>> 4 H
1 O >>>>>>>>>>>> 2 O
Thus, the above equation is not balanced.
For Option D:
Na + 2H2O —> NaOH + 2H2
Reactant >>>>>>> Product
1 Na >>>>>>>>>>> 1 Na
4 H >>>>>>>>>>>> 5 H
2 O >>>>>>>>>>>> 1 O
Thus, the above equation is not balanced.
From the illustrations made above, only option A is balanced.
