In Lab H2SO4 solution is prepared by dissolving 4.9 grams of H2SO4 in 100mL of water a. How many h2SO4 molecules are in this solution b. What is the molarity of the soltuion c. What is the pH of the solution d. What is the pH of the solution if 3.0 grams of NaOH is added to the solution

Part (a) The number of molecules of H₂SO₄ in the solution is 3.011 X 10²² molecules

Part (b) the molarity of the solution is 0.5 M

Part (c) the pH of the solution is 0

Part(d) the pH of the solution is 13.87

Explanation:

Part (a) How many H₂SO₄ molecules are in this solution

number of moles = Reacting mass/molar mass

Molar mass of H₂SO₄ = (2x1 + 32 + 4X16) = 98 g/mol

      number of moles = 4.9/98 = 0.05 mol.

I mole =  6.022 x 10²³ molecules

0.05 mole = (0.05 X 6.022 x 10²³) molecules

= 3.011 X 10²² molecules

Part (b) What is the molarity of the solution

molarity = moles of solute/liters of solution

molarity = 0.05/(100 x 10⁻³ L)

molarity = 0.5 M

Part (c) What is the pH of the solution

H₂SO₄ ⇄ 2H⁺ + SO₄²⁻

pH = -Log[2H⁺]

pH = -Log[2*0.5]

pH = -Log[1]

pH = 0

Part(d) What is the pH of the solution if 3.0 grams of NaOH is added to the solution

molar mass of NaOH = ( 23 + 16 +1) = 40g/mol

Number of moles = 3/40 = 0.075 moles

molarity = 0.075/(100 x 10⁻³ L)

molarity = 0.75 M

pOH = - Log[OH⁻]

pOH = - Log[0.75]

pOH = 0.13

Also, pH + pOH = 14

pH = 14 - pOH

pH = 14 - 0.13

pH = 13.87

assuming that your periodic table has eighteen columns, you should highlight   the four elements in the third column from the left of the table.

neutral atoms of elements after calcium contain d electrons. the energy of d orbitals of a particular main shell lies between the energy of the s and p orbitals of the next main shell. for example, electrons in the have energy higher than those in the orbital while lower than those of the orbital.

by the aufbau principle, electrons fill orbitals one at a time, starting from those of the lowest energy. the orbital is therefore filled right after orbitals and before orbitals.  

potassium has electron configuration and calcium . the s orbital of a main shell holds a maximum of two electrons. the next element would thus have the electron configuration and satisfy the requirements.

a neutral atom of the element contains three electrons on top of the most recent noble gas element. it should thus be placed in the third column of the periodic table. both scandium and yttrium would satisfy the conditions. an aufbau diagram indicates that the 4f orbital is filled before the 5d. however, it appears that exceptions exists for both lanthanum and actinium. neutral atoms of the two d-block elements also demonstrate the and should be highlighted as well.