What do you need help with. I am very good at chemistry.
<u>Answer:</u>
<em>0.264 g of
can be formed from 288 mg of
</em>
<u>Explanation:</u>
The balanced chemical equation is

The conversions are
Mass in mg
is converted to mass in g
Mass in g
is converted to moles
by dividing with molar mass
Moles
is converted to moles
by using the mole ratio of
is 9 : 6
Moles
is converted to mass
by multiplying with molar mass 
mass in mg
> mass in g
>moles
> moles
> mass 

=0.264g (Answer)
Answer: 12.78ml
Explanation:
Given that:
Volume of KOH Vb = ?
Concentration of KOH Cb = 0.149 m
Volume of HBr Va = 17.0 ml
Concentration of HBr Ca = 0.112 m
The equation is as follows
HBr(aq) + KOH(aq) --> KBr(aq) + H2O(l)
and the mole ratio of HBr to KOH is 1:1 (Na, Number of moles of HBr is 1; while Nb, number of moles of KOH is 1)
Then, to get the volume of a 0.149 m potassium hydroxide solution Vb, apply the formula (Ca x Va)/(Cb x Vb) = Na/Nb
(0.112 x 17.0)/(0.149 x Vb) = 1/1
(1.904)/(0.149Vb) = 1/1
cross multiply
1.904 x 1 = 0.149Vb x 1
1.904 = 0.149Vb
divide both sides by 0.149
1.904/0.149 = 0.149Vb/0.149
12.78ml = Vb
Thus, 12.78 ml of potassium hydroxide solution is required.
There are 3 moles of

<span>per 1 mole of salt and 1 mole of

</span>per mole of salt, the total ionic concentrations must be

of

, and

of