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Chemistry

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A student wishes to determine the concentration of sulfuric acid. They run a titration and discover that 62.5cm^3 is needed to neutralise 20cm^3 of sodium hydroxide of concentration 2moldm^-3. Work out the concentration of the acid.

To answer this question the first thing that needs to be done is to write a chemical equation, making sure it is balanced and includes state symbols:H2SO4 (aq) + 2NaOH (aq) --> Na2SO4 (aq)+ 2H2O (l)Nex...

Answered by Ellen C. • Chemistry tutor

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In aqueous solution, sulphuric acid dissociates into ions in 2 stages. The pKa for the first dissociation is -3. Calculate the pH of a 0.025 mol dm-3 solution of sulphuric acid using the pKa value of the 1st dissociation.

Ka = 10^-pKa = 10^--3 = 1000[H⁺] = √ Ka [0.025] = √1000 x 0.025 = 0.791pH = -log [H] = -log(0.791) = 0.102 = 0.1

Answered by Octavia M. • Chemistry tutor

1968 Views

Balance the equation C4H8 + O2 ->CO2 + H2O

C₄H₈ + O₂ -> CO₂ + H₂O
Want to deal with only one element at the time, recap that you can only add coefficients to the front of chemical fo...

Answered by Claire D. • Chemistry tutor

12938 Views

Magnesium has 12 as its atomic number, how many protons does it have?

12 -the proton number of an atom is also its atomic number

Answered by Jacob J. • Chemistry tutor

2245 Views

An isotope of Nitrogen has an atomic number of 7 and a mass number of 15. How many electrons, neutrons, and protons does an atom of this isotope have?

Atomic number = the number of protons per atom of this isotopeMass number = total number of protons + neutrons per atom
Therefore, an atom of this isotope has 7 protons and 15-7=8 neutrons.
As ...

Answered by Sophie I. • Chemistry tutor

7986 Views