A chemist dissolves 751.mg of pure nitric acid in enough water to make up 290.mL of solution. Calculate the pH of the solution. Be sure your answer has the correct number of significant digits.

1.4

Explanation:

Mass of pure nitric acid = 751mg

Volume of solution  = 290mL

Unknown:

pH of the solution  = ?

Solution:

To solve this problem, we need the concentration of the acid in the aqueous form.

   This is given by molarity;

               Molarity  =

Since the number of moles of nitric acid is unknown, we can easily solve for it.

      Number of moles of nitric acid  =

            molar mass of HNO₃   =  1 + 14 + 3(16)  = 63g/mol

             mass of nitric acid  = 751mg  = 0.751g

     Number of moles  =    = 0.012mole

Volume of solution = 290mL  = 0.29dm³

Now molarity of the solution  =   = 0.041moldm⁻³

Since:

     pH  = -log [H₃O⁺]

         HNO₃   +     H₂O  →    H₃O⁺         +         NO₃⁻

      1moldm⁻³                     1moldm⁻³            1moldm⁻³

   0.041moldm⁻³             0.041moldm⁻³    0.041moldm⁻³

  pH  = -log[0.041]   = 1.4

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

            and  

since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.  

the correct answer is b. a strong acid completely dissociates to its ions when dissolved in water. completely dissociates to and ions. a is incorrect because does not fully ionize to and ions and some remain as the compound . c and d are incorrect because, and do not fall into the category of bronsted lowry acids. a bronsted lowry acid is a proton donor and since both molecules do not have a proton to donate they are not bronsted lowry acids. likewise,   if we use the lewis acid definition, they cannot be acids. a lewis acid is an electron pair acceptor. both and have a complete octet so can not accept any electrons which disqualifies them as acids.