Answer:
The correct answer is 0.36 mol
Explanation:
First we have to calculate the molecular weight (Mw) of H₃BO₃ from the molar masses of the elements:
Mw(H₃BO₃)= 3 x Molar mass H + Molar mass B + (3 x Molar mass O)
= 3 x 1 g/mol + 10.8 g/mol + (3 x 16 g/mol)
= 61.8 g/mol
The molecular weight indicates that there are 61.6 grams per mol of substance. The scientist has 22.5 g, thus we can calculate the number of moles of H₃BO₃ by dividing the mass into the molecular weight as follows:
Number of moles of H₃BO₃ = mass/Mw= (22.5 g)/(61.8 g/mol) = 0.36 mol
There are 0.36 mol of H₃BO₃ in 750.0 mL of solution.
In decomposition, two or more reactant combine to form one product only.
Explanation:
The given data for case (1) is as follows.
h = 20 cm = 0.2 m
Assuming that a rectangular slab is placed above the pipe and we will calculate the heat transfer as follows.
Q =
where, A = area
L = length
k = thermal conductivity = 0.8 W/m
= change in temperature.
Therefore, putting the given values into the above formula as follows.
Q =
=
= 168 W
For case (2), h = 180 cm = 1.8 m
Therefore, heat lost will be calculated as follows.
Q =
=
= 18.67 W
Thus, we can conclude that 18.67 W heat lost if the pipe was buried at a depth of 180 cm.
In eukaryotic cells the citric acid cycle takes place in the matrix of the mitochondria.