To solve this we assume that the gas inside the
balloon is an ideal gas. Then, we can use the ideal gas equation which is
expressed as PV = nRT. At a constant pressure and number of moles of the gas
the ratio T/V is equal to some constant. At another set of condition of
temperature, the constant is still the same. Calculations are as follows:
T1 / V1 = T2 / V2
V2 = T2 x V1 / T1
V2 = 231 x 556 / 278
V2 = 462 cm³
Answer:
180 mg
Explanation:
For a first-order reaction, we can calculate the amount of aspirine (A) at a certain time (t) using the following expression.
where,
k: rate constant
A₀: initial amount
If we know the half-life () we can calculate the rate constant.
When t = 4 h and A₀ = 400 mg, A is:
Answer:
0.412mol/Kg
Explanation:
First, let us fine the number of mole of KCl.. This is illustrated below
Mass of KCl = 15.434g
Molar Mass of KCl = 74.55 g/mol
Number of mole = Mass /Molar Mass
Number of mole KCl = 15.434/74.55 = 0.21mole
Now, let us calculate the mass of the water in kg. This can be achieved by doing the following:
Density = 1.02 g/mL
Volume = 500mL
Mass =?
Mass = Density x volume
Mass of water = 1.02 x 500 = 510g
Converting 510g to kg, we have: 510/1000 = 0.51kg
Now we calculate for the molality as follows:
Mole of the solute = 0.21mole
Mass of the solvent = 0.51Kg
Molality = mole of solute /mass of solvent
Molality = 0.21/0.51
Molality = 0.412mol/Kg
Calculate the number of moles for each element. n=m/M Then compare, and which ever one is lowest is the limiting reactant because no more products can form without one or the other.