The molarity of a solution is the number of moles of a substance per liter of the solution.
400 mL becomes 0.400 liters
You have 0.0345 moles of ammonium chloride NH4Cl, so take the number of moles over the number of liters to find the answer.
0.0345 moles/0.400 liters = 0.0863 moles/liter
0.0863M = molarity of the solution
The quantity pH stands for the negative logarithm of the H⁺ ions concentration in a solution. In equation form, pH = -log[H⁺], where [H⁺] is the concentration of hydrogen ion in molarity or moles/liter. Using this definition, the pH of the following substances are:
Oven Cleaner: pH =-log(10⁻¹³ M) = 13
Water: pH = -log(<span>0.0000007 M) = 6.15
Blood: pH = -log(</span><span>0.00000004 M) = 7.40
Vinegar: pH = -log(</span><span> 0.0063 M) = 2.2
The measure of the pH is important when it comes to reactions because pH is a strong factor. The net charge of a substance is a result of its pH. This charge is the basis of the degree of intermolecular forces like electrostatic attraction due to difference of charges by the substance and its substrate.</span>
If this is for homework then eat lots of bacon.
A half life of 29 years means that after 29 years, only half of this isotope would be left due to radioactive decay. If we start of with 2000g of it and leave it for 116 years, it would undergo 4 "half=lives". 116/29 = 4. So after the first half life, we would have 2000g/2 = 1000g left. After the second, we would have 500g left, after the third, 250g so after 4 half lives or 116 years, there would be 125 g of Strontium-90 left at the site.
