First, we need to calculate moles of hydrazoic acid NH3:
moles NH3 = molarity * volume
= 0.15 m * 0.025 L
= 0.00375 moles
moles NaOH = molarity * volume
= 0.15 m * 0.015 L
= 0.00225 moles
after that we shoul get the total volume = 0.025L + 0.015L
= 0.04 L
So we can get the concentration of NH3 & NaOH by:
∴[NH3] = moles NH3 / total volume
= 0.00375 moles / 0.04 L
= 0.09375 M
∴[NaOH] = moles NaOH / total volume
= 0.00225 moles / 0.04 L
= 0.05625 M
then, when we have the value of Ka of NH3 so we can get the Pka value from:
Pka = -㏒Ka
= - ㏒ 1.9 x10^-5
= 4.7
finally, by using H-H equation we can get PH:
PH = Pka + ㏒[salt/ basic]
PH = 4.7 +㏒[0.05625/0.09375]
∴ PH = 4.48
Answer:
The process of dissolving increases entropy because the solute particles become separated from one another when a solution is formed.
D, the lava from the volcano can reach water and make new land
Answer:
d = 0.84 g/cm³
Explanation:
Given data:
Mass of wood = 2.85 g
Volume of water = 20.0 mL
Volume of water + wood = 23.4 mL
Density of wood = ?
Solution:
Volume of wood = (Volume of water + wood ) - Volume of water
Volume of wood = 23.4 mL - 20.0 mL
Volume of wood = 3.4 mL
1 mL = 1 cm³
Density of wood:
d = m/v
d = 2.85 g / 3.4cm³
d = 0.84 g/cm³
Answer:
337.5 g NaCl
Explanation:
.90% saline solution = 90g saline (NaCl)/100mL water (H2O)
1. Use 375 mL to find mass
375 mL × (90 g NaCl/100 mL) = 337.5 g NaCl in 375 mL .9% saline solution