First calculate mass of sodium hydrogen phosphate (Na₂HPO₄) needed for solution:
n(Na₂HPO₄) = V(Na₂HPO₄) · c(Na₂HPO₄)
n(Na₂HPO₄) = 0,3 dm³ · 0,2 mol/dm³
n(Na₂HPO₄) = 0,06 mol
m(Na₂HPO₄) = 0,06 mol · 142 g/mol
m(Na₂HPO₄) = 8,52 g.
Measure that mass on scale using spoon and beaker. Than dissolve salt in beaker with distilled <span>water and pour that solution in volumetric flask (size 300 mL), pour </span>distilled water to graduation<span> mark.</span>
Answer:
Explanation:
1. Increasing the concentrations of reactants in a chemical reaction would affect a reaction positively by increasing the number of collisions within a particular period which in turn increases the rate of reaction.
2. The molecules gains energy,which enable them to move faster and collide with the right energy for a reaction to take place.
3. The average kinetic motion of molecules in a solution can be measured by measuring the temperature. Temperature is a measure of the average kinetic energy of molecules in a solution.
Answer:
Degree of ionization = 0.0377
pH of the solution = 1.769
Explanation:
Initial concentration of HF = 0.45 M
Initial 0.45 0 0
At equi 0.45 - x x x
Equilibrium constant = ![\frac{[H^+][F^-]}{HF}](https://tex.z-dn.net/?f=%5Cfrac%7B%5BH%5E%2B%5D%5BF%5E-%5D%7D%7BHF%7D)
![6.8 \times 10^{-4}= \frac{[x][x]}{0.45 - x}](https://tex.z-dn.net/?f=6.8%20%5Ctimes%2010%5E%7B-4%7D%3D%20%5Cfrac%7B%5Bx%5D%5Bx%5D%7D%7B0.45%20-%20x%7D)
x = 0.017 M
x = Cα
α = Degree of ionization
C = Concentration
Degree of ionization = 
![pH = -log[H^+]](https://tex.z-dn.net/?f=pH%20%3D%20-log%5BH%5E%2B%5D)
[H^+]=0.017 M
![pH = -log[0.017]](https://tex.z-dn.net/?f=pH%20%3D%20-log%5B0.017%5D)
= 1.769
Answer:
False
Explanation:
It is important to give exact measurements.
