Answer:
1. (NH₄)₂S(s) -----> NH₄+(aq) + S²-(aq)
2. Al³+ (aq) + PO₄³+ (aq) ----> AlPO₄ (s)
Explanation:
The dissociation of ammonium sulphide, (NH₄)₂S when dissolved in water is given in the equation below:
(NH₄)₂S(s) -----> NH₄+(aq) + S²-(aq)
However very little S²- ions are present in solution due to the very basic nature of the S²- ion (Kb = 1 x 105).
The ammonium ion being a better proton donor than water, donates a proton to sulphide ion to form hydrosulphide ion which exists in equilibrium with aqueous ammonia.
S²- (aq) + NH₄+ (aq) ⇌ SH- (aq) + NH₃ (aq)
Aqueous solutions of ammonium sulfide are smelly due to the release of hydrogen sulfide and ammonia, hence, their use in making stink bombs.
2. The reaction between aluminium nitrate and sodium phosphatein aqueous solution is a double decomposition reaction whish results in the precipitation of insoluble aluminium phosphate. The equation of the reaction is given below :
Al(NO₃)₃ (aq) + Na₃PO₄ (aq) ----> AlPO₄ (s) + 3 NaNO₃ (aq)
The net ionic equation is given below:
Al³+ (aq) + PO₄³+ (aq) ----> AlPO₄ (s)
Answer:
Option A = atomic masses
Explanation:
In compound molecular mass is the sum of the individual atomic masses of the atoms.
For example
Compound NaCl.
atomic weight of sodium = 23 g/mol
atomic weight of chlorine = 35.5 g/mol
Molar mass of NaCl = 23+ 35.5 = 58.5 g/mol
Every atom consist of nucleus or a positive center. The protons and neutrons are present with in the nucleus while electrons are present out side the nucleus. All these three subatomic particles construct an atom. The number of protons or number of electrons are the atomic number of an atom while the number of protons and number of neutrons are the mass number of an atom. A neutral atom have equal number of protons and electrons. In other words we can say that negative and positive charges are equal in magnitude and cancel the each other.
Explanation:
element with atomic numbers 7 and 83 have 5 and 5 valence electrons
Answer:
a. N₂O₅ + H₂O ⇒ 2 HNO₃ (pentóxido de dinitrógeno + agua ⇒ ácido nítrico)
b. Na₂O + H₂O ⇒ 2 NaOH (óxido de sodio + agua ⇒ hidróxido de sodio)
Explanation:
Tenemos que balancear, por el método de tanteo, las siguientes ecuaciones químicas.
a. En la primera reacción, el pentóxido de dinitrógeno reacciona con agua para formar ácido nítrico. Es una reacción de síntesis o combinación.
N₂O₅ + H₂O ⇒ HNO₃
Podremos obtener la ecuación balanceada si multiplicamos HNO₃ por 2.
N₂O₅ + H₂O ⇒ 2 HNO₃
b. En la segunda reacción, óxido de sodio reacciona con agua para formar hidróxido de sodio. Es una reacción de síntesis o combinación.
Na₂O + H₂O ⇒ NaOH
Podremos obtener la ecuación balanceada si multiplicamos NaOH por 2.
Na₂O + H₂O ⇒ 2 NaOH