Supposing a temperature of 25 degrees and supposing that all
activity coefficients are 1
pH = -log[H+]
pOH = -log[OH-]
pH + pOH = 14
Thus a pH of 2.50 would mean that the [H+], the concentration of the hydrogen
ion, would be 10^(-2.50)
pH + pOH = 14
pOH = 14 - pH = 14 - 2.5 = 11.5
MOH- levels would be coordinated with pOH
pOH = -log[OH-] ==> [OH-] = [MOH-] = 10^-pOH = 10^-11.5 = 3.2 x 10^-12
Therefore, MOH¯ = 3.2 × 10¯12 M
Molality is one way of expressing concentration for solutions. It has units of moles of solute per kg of solvent. From the given values, we easily calculate for the moles of solute by multiplying the mass of solvent to the molality. We do as follows:
moles solute = 0.3 (10) = 3 mol solute
Heat required = M * C * (delta T)
= (Mass)*(Specific heat)*(temperature change)
= 250 * 4.18* 52 = 54340Joules.
I solve when unit of specific heat is (J/gC) if have another unit please tell me
Radioactive decay is a pseudo-first order reaction. When you know the half-life of the material, you could use this equation.
A= A₀(1/2)^t/h
where
A is the final activity
A₀ is the initial activity
t is the time
h is the half-life
A = (0.64)(1/2)^88/44 = <em>0.16 mbq</em>
