Answer:-
KOH determines how much Mg(OH)2 is made.
2 mol of Mg(OH)2 formed
Explanation:-
The balanced equation is
MgCl2 + 2KOH --> Mg(OH)2+ 2KCI,
From seeing the coefficients we notice
2 mol of KOH reacts with 1 mol of MgCl2
4 mol of KOH reacts with 1 x 4 / 2 = 2 mol of MgCl2
3 moles of MgCl2 was added but only 2 mol react.
So we see there is excess MgCl2 .
Hence KOH is the limiting reactant.
So KOH determines how much Mg(OH)2 is made.
We see from the balanced chemical equation,
2 mol of KOH gives 1 mol of Mg(OH)2.
4 mol of KOH will give 1 x 4 /2 = 2 mol of Mg(OH)2.
Answer:
Light bulbs
Explanation:
light waves are electromagnetic waves which can travel through a vacuum
Answer:
A precipitate will be formed
Explanation:
The Ksp equilibrium of Fe(OH)₃ is:
Fe(OH)₃ (s) ⇄ Fe³⁺(aq)+ 3OH⁻(aq)
And its expression is:
Ksp = 4x10⁻³⁸ = [Fe³⁺] [OH⁻]³
<em>Where the concentrations are concentrations in molarity in equilibrium,</em>
We can write Q as:
Q = [Fe³⁺] [OH⁻]³
<em>Where [] are actual concentrations in molarity of each specie.</em>
<em />
When Q>= Ksp; a precipitate is formed,
When Q< Ksp no precipitate is produced:
[OH⁻] = [NaOH] = 1.0x10⁻⁴M
[Fe²⁺] = 2.50x10⁻²g * (1mol / 179.85g) / 0.100L = 1.39x10⁻³M
<em>179.85g/mol is molar mass of Fe(NO₃)₂ and the volume of the solution is 0.100L = 100mL</em>
<em />
Q = [Fe³⁺] [OH⁻]³
Q = [ 1.39x10⁻³] [ 1.0x10⁻⁴]³
Q = 3.8x10⁻¹⁵
As Q >> Ksp; A precipitate will be formed
It would change the charge, a neutral atom has zero charge but a proton has a positive charge. So 0 charge + 1 positive charge = 1 positive charge.
First, take the molar mass of B (10.81g) and divide the value you've been given by the molar mass to get moles (5.4 / 10.81). So you have .5 moles of B and then you need to convert that to atoms. To do that you must use the constant 6.022X10^23 atoms per mole. Take your moles and multiply it by that constant. Your final answer should be (3.01X10^23) atoms.
Hope this helps!
