The balanced chemical reaction is given above however I believe the coefficients are wrong. It should be:
4K + O2 = 2K2O
We use data from that reaction to obtain relationships between substances. We are given the amount of potassium that reacts. We proceed as follows:
1.52 mol K ( 2 mol K2O / 4 mol K ) = 0.76 mol of K2O is formed
Answer:
Zn(s) + 2H₂O (l) → Zn(OH)2(aq) + H2(g)
Sn(s) + O2(g) →SnO2(s)
Cd(s) + Pb(NO3)2 (aq) →Cd(NO3)2 (aq) + Pb(s)
Cu (s) + HCl(aq) → can not occur
Explanation:
Metals reacts with liquid water to yield the corresponding metallic hydroxide and hydrogen gas as shown above; Zn(s) + 2H₂O (l) → Zn(OH)2(aq) + H2(g)
Tin reacts with oxygen to yield tin (IV) oxide. This is an oxidation reaction as shown; Sn(s) + O2(g) →SnO2(s)
The reaction between Cd and Pb(NO3)2 is a single replacement reaction. It is possible because Cd is above Pb in the electrochemical series. Hence the reaction occurs thus; Cd(s) + Pb(NO3)2 (aq) →Cd(NO3)2 (aq) + Pb(s)
Copper does not displace hydrogen from dilute acids (such as HCl) since copper is lower than hydrogen in the electrochemical series hence the reaction does not occur.
Sodium, Sulphur, and Oxygen