<em>Answer:</em>
- PbS are not soluble in water.
<em>Solubility rule:</em> "<em>Like dissolve like</em>"
<em>Reason of insolubility of PbS.</em>
- When sulphides are attached with group one and group two elements of periodic table, they are soluble but when they are attached with transition metals like Pb, there is highly covalent bond which makes difficult dissociation of bonds in water.
- KClO2 and NH4Br are inoic substances , so they are easily soluble. HNO2 is weak acid which can ionize in water.
Answer:
Lithium selenide Lithium selenide (Li2Se) 12136-60-6 Dilithium selenide lithium selenidolithium
Molecular Weight 92.9 g/mol
Dates Modify 2020-11-15 Create 2005-08-08
Answer:
380g
Explanation:
Given parameters:
Number of moles of Fluorine = 20moles
Unknown:
Mass of Fluorine = ?
Solution:
The number of moles is the unit of quantifying the amount of particles in a substance.
So;
Mass of a substance = number of moles x molar mass
Molar mass of F = 19g/mol
Now;
Mass of F = 20 x 19 = 380g
Answer:- 448 mL of hydrogen gas are formed.
Solution:- It asks to calculate the volume of hydrogen gas formed in milliliters at STP when 0.020 moles of magnesium reacts with excess HCl acid. The balanced equation is:
There is 1:1 mol ratio between Mg and hydrogen gas. So, the moles of hydrogen gas is also equals to the moles of Mg reacted.
moles of Hydrogen gas formed = 0.020 mol
At STP, volume of 1 mol of the gas is 22.4 L. We need to calculate the volume of 0.02 moles of hydrogen gas.
= 0.448 L
They want answer in mL. So, let's convert L to mL using the conversion formula, 1L = 1000mL
= 448 mL
So, 0.020 moles of magnesium would produce 448 mL of hydrogen gas at STP on reacting with excess of HCl acid.
so:
so:
it means that
in
of acid there is
moles of acid
so:
it means that:
in
of water there is
moles of water
therefore:
So your answers are:
and the mole fraction is: