Select one or more:
a. Chlorine forming a solid precipitate
b. Bubbles forming from hydrogen gas production
c. Solid zinc dissolving
d. Bubbles forming from chlorine gas production
B) copper
C) methane
D) rust
It is B. I took the test!!
Monopoly GO! bye bye guys i gtg
Answer:
Initial concentration of acetic acid (CH3COOH_initial): 0.25 M
pKa for acetic acid: 4.76
Assume x is the concentration of H+ ions formed through dissociation.
CH3COOH ⇌ x (due to dissociation)
Apply the x-is-small approximation: We assume x is much smaller than the initial concentration of acetic acid (0.25 M). Therefore, we can neglect x in comparison to 0.25 M.
Calculate pH using the pKa equation:
Rounded to two decimal places, the pH of the acetic acid solution is approximately 2.68.
Explanation:
Hello!
An antacid tablet containing 0.50 g of NaHCO3 is dissolved in 250 mL of water. What is the molar concentration of NaHCO3 in the solution ?
M (Molar Concentration or Molarity) = ? (in mol/L)
m (mass) = 0.50 g
V (volume) = 250 mL → 0.25 L
MM (Molar Mass of NaHCO3)
Na = 1*(23u) = 23 u
H = 1*(1u) = 1 u
C = 1*(12u) = 12 u
O = 3*(16u) = 48 u
-------------------------------
MM (Molar Mass of NaHCO3) = 23 + 1 + 12 + 48 = 84 g/mol
Answer:
The Molar Concentration is approximately 0.024 mol/L
________________________
B. Higher
Lower Temperature
The boiling point is defined as the temperature at which the vapor pressure of a given liquid becomes equal to the external pressure or atmospheric pressure. Boiling point is mainly effected by following factors:
1) Inter-Molecular Interactions:
Greater the intermolecular interactions greater will be the boiling point because more energy is required to overcome these intermolecular interactions.
Example:
Water = 100 °C
Diethyl ether = 34.5 °C
Water requires more energy because it contains hydrogen bond interactions which are considered the strongest intermolecular interactions. While, Diethyl ether lacks Hydrogen bondings.
2) External Pressure:
The boiling point also varies with changing the external pressure for the same solvent. Greater the external pressure greater will be the boiling points and vice versa.
Example:
Water:
External Pressure Boiling Point
1 atm 100 °C
0.921 atm 98 °C
0.425 atm 72 °C