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:
E = 5.69x10⁻²⁸m
Explanation:
To solve this question we neeed to convert the wavelength in meters to energy in joules using the equation:
E = hc / λ
<em>Where E is energy in joules, h is Planck's constant = 6.626x10⁻³⁴Js</em>
<em>c is light constant = 3.0x10⁸m/s</em>
<em>And λ is wavelength in meters = 349m</em>
Replacing:
E = 6.626x10⁻³⁴Js*3.0x10⁸m/s / 349m
E = 5.69x10⁻²⁸m
Answer:
The proportion of dissolved substances in seawater is usually expressed in ppm, ppb or ppt
Explanation:
The concentration of very diluted solutions should be expressed in parts per million, billion or trillion.
ppm = mass from the solute . 10⁶ / mass or volume of the solution
ppb = mass from the solute . 10⁹ / mass or volume of the solution
ppt = mass from the solute . 10¹² / mass or volume of the solution
ppm = mg/kg, μg/g, μg/mL → These are the units
ppb = ng/g
ppt = pg/g
Answer:
Like most other metals, Gallium is solid at room temperature (or liquid if it is too hot in your room). But, if it is held [in hands] for long enough, it melts in your hands, and doesn't poison you like Mercury would. This is because of its unusually low melting point of (~29 degree Centigrade).
- It melts once it reaches its melting point.
:)
739 is the number of atoms of O in 92.3 moles of Cr3(PO4)2.
Explanation:
Molecular formula given is = Cr3(PO4)2
number of moles of the compound is 92.3 moles
number of 0 atoms in 92.3 moles =?
From the chemical formula 1 mole of the compound has 8 atoms of oxygen
So, it can be written as
1 mole Cr3(PO4)2 has 8 atoms of oxygen
92.3 moles of Cr3(PO4)2 has x atoms of oxygen
=
x = 8 x 92.3
x = 738.4 atoms
There will be 739 oxygen atoms in the 92.3 moles of Cr3(PO4)2.