Burette readings (initials and final) must be given to two decimal places. Volume of pipette used must also be recorded but no account experimental procedure is required. Al calculations must be done in your answer book. A solution containing 0.05moldm\(^3\) H\(_2\)SO\(_4\). B is a solution containing 1.4g per 250cm\(^3\) .XOH
(a) Put A into the burette and titrate it against 20.0cm\(^3\) or 25.0cm\(^3\) portions of B using methyl orange indicator. Repeat the titration to obtain consistent titres. Tabulate your results and calculate the average volume of A used. The equation for the reaction involved in the titration is; H\(_2\)SO\(_{4(aq)}\) + 2XOH\(_{(aq)}\) \(\to\) X\(_2\)SO\(_{4(aq)}\) + 2H\(_2\)O\(_{(l)}\)
(b) From your results and the information provided above, calculate the;
(i) concentration of B in moldm\(^{-3}\)
(ii) molar mass XOH
(iii) relative atomic mass of X. [H = 1.00; O = 16.0 S =32.0]
(a) Explain briefly the observations in each of the following processes:
(i) when carbon (IV) oxide is bubbled through lime water, It turns milky but the milkiness disappears when the gas is bubbled for a long time.
(ii) A precipitate of calcium hydroxide is insoluble in excess sodium hydroxide solution whereas that of lead (ii) hydroxide is soluble
(b)(i) What is a primary standard solution?
(ii) Calculate the mass of sodium trioxocarbonate (V) required to prepare 250 cm\(^3\) of 0.15gmoldm\(^3\) solution hydroxide is soluble. [Na = 23.0; O = 16.0; C = 12.0]
(c) Name one gas that can be collected by
(i) upward displacement of air
(ii) downward displacement of air
Credit will be given for strict adherence to the instructions, for observations precisely recorded, and for accurate inferences. All tests, observations, and inferences must be clearly entered in your answer book, in ink, at the time they are made.
C and D are two aqueous solutions. Carry out the following exercises on C and D. Record your observations and identify any gas(es) evolved. State the conclusion you draw from the result of each test.
(a)(i) To about 2 cm\(^3\) portion of C, add NaOH\(_{(aq)}\) In drops until in excess. Warm the mixture
(ii) To another 2 cm\(^3\) portion of C, add HCl\(_{(aq)}\) followed by BaCl\(_{2(aq)}\)
(b)(i) (ii) To another 2 cm\(^3\) portion of D, add add NH\(_{3(aq)}\) drops and then in excess.
(ii) To about 2 cm\(^3\) portion of D, add AgNO\(_{3(aq)}\) followed by HNO\(_{3(aq)}\)
Burette readings (initial and final) must be given to two decimal places. Volume of pipette used must also be recorded but no account of experimental procedure is required. All calculations must be done in your answer book.
A solution containing 6.22 g of an acid H\(_2\)Y per dm\(^3\)
B contains 3.90 g of NaOH per dm\(^3\) of solution.
(a) Put A into the burette and titrate it against 20.0 cm\(^3\) or 25.0 cm\(^3\) portions of B using methyl orange as indicator. Repeat the titration to obtain consistent titres. Tabulate your burette readings and calculate the average volume of acid A used. The equation for the reaction involved in the titration is:
H\(_2\)\(_{(aq)}\) + 2NaOH\(_({aq})\) \(\to\) NaY\(_{(aq)}\) + 2H\(_2\)O\(_{(l)}\)
[H = 1.00; O = 16.0; Na = 23.0]
(b) From your results and the information provided above, calculate the:
(i) The concentration of B in moldm\(^{-3}\)
(ii) concentration of A in moldm\(^3\)
(ii) molar mass of H\(_2\)Y.
(c) State whether the pH of each of the following solutions is lower than 7, greater than 7 or equal to 7. The
(I) solution A before titration
(ii) solution B before titration
(a) A colourless gas P was given off when dilute tetraoxosulphate (VI) acid was added to zinc salt Q. On bubbling the gas through lime water, a white precipitate R was formed. Identify P, Q and R.
(b) Name a suitable apparatus that could be used to perform each of the following activities in the laboratory
(i) storage of dilute silver trioxonitrate (V):
(ii) heating copper metal;
(iii) separation of a mixture of water and Kerosene. Give one reason for each of your answers in (b)
