Answer: 159 grams
Explanation:
Copper (ii) oxide has the chemical formula CuO.
Now given that:
Mass of CuO in grams = ? (let unknown value be Z)
Number of moles = 2.00 moles
Molar mass of CuO = ?
For the molar mass of CuO: Atomic mass of Copper = 63.5g ; Oxygen = 16g
= 63.5g + 16g
= 79.5 g/mol
Apply the formula:
Number of molecules = (mass in grams/molar mass)
2.00 moles = (Z / 79.5 g/mol)
Z = 79.5 g/mol x 2.00 moles
Z = 159g
Thus, there are 159 grams in 2.00 moles of copper (ii) oxide
Answer:
1.94 × 10⁻³
Explanation:
Step 1: Calculate the concentration of H⁺ ions
We will use the definition of pH.
pH = -log [H⁺]
[H⁺] = antilog -pH = antilog -2.32 = 4.79 × 10⁻³ M
Step 2: Calculate the acid dissociation constant (Ka) of the acid
For a monoprotic weak acid, whose concentration (Ca) is 0.0118 M, we can use the following expression.
Ka = [H⁺]²/Ca
Ka = (4.79 × 10⁻³)²/0.0118 = 1.94 × 10⁻³
B, some ionic bonds are too strong for the attractions of water molecules to pull them apart
