"NH4+ <----> NH3 + H+
The constant of this equilibrium is: K = Kw / Kb = 1 x 10^-14 / 1.8 x 10^-5 =5.56 x 10^-10
5.56 x 10^-10 = x^2 / 0.20-x
x = [H+] =1.1 x 10^-5 M
pH = 5.0"
Answer: 10 uses
Explanation:
1] Oxygen is used for breathing.
2] Chlorine is used for purifying water.
3] Phosphorous is used in crackers.
4] Non - metals like nitrogen is used in fertilizers.
5] Graphite is used as a good conductor of electricity.
6] Pottassium is used in fertilizers.
7] Nitrogen is used by plants.
8] Graphite is used in making leads.
9] Carbon is used as a fuel.
10] Bromine is used in dyes and pesticides
The correct answer is (1) one mole of NO2.
The gram formula mass is also known as the molar mass and is defined by the mass over one mole of a substance.
Hope this helps~
Answer:
CH₃CH₂CH₂COOH > CH₃CH₂COOH > ClCH₂CH₂COOH > ClCH₂COOH
Explanation:
Electron-withdrawing groups (EWGs) increase acidity by inductive removal of electrons from the carboxyl group.
Electron-donating groups (EDGs) decrease acidity by inductive donation of electrons to the carboxyl group.
- The closer the substituent is to the carboxyl group, the greater is its effect.
- The more substituents, the greater the effect.
- The effect tails off rapidly and is almost zero after about three C-C bonds.
CH₃CH₂-CH₂COOH — EDG — weakest — pKₐ = 4.82
CH₃-CH₂COOH — reference — pKₐ = 4.75
ClCH₂-CH₂COOH — EWG on β-carbon— stronger — pKₐ = 4.00
ClCH₂COOH — EWG on α-carbon — strongest — pKₐ = 2.87
Answer: 20 mg Te-99 remains after 12 hours.
Explanation: N(t) = N(0)*(1/2)^(t/t1/2)
N(t) = (80 mg)*(0.5)^(12/6)
N(t) = 20 mg remains after 12 hours
