Miracle Learning Centre Chemistry Tuition Question on Redox Reactions. (O Level Chemistry Tuition/ IP Chemistry Tuition)

1. The exhaled breath of diabetics contains propanol. A medical student wishes to test for diabetes by asking patients to bubble their breath through a reagent. Which reagent could be used? A aqueous bromine B acidified potassium dichromate (VI) solution C universal indicator D aqueous potassium iodide

2. In the following reaction: MnO2 + 4HCl  MnCl2 + 2H2O + Cl2 The substance HCl is reacting as A a catalyst. B a dehydrating agent. C an oxidising agent. D a reducing agent.

3. In which of the following is the oxidation number (oxidation state) of chromium greater than that of manganese? A K2Cr2O7 MnO4 B Cr2O3 MnO2 C K2CrO4 KMnO4 D Cr2(SO4)3 MnSO4 Miracle Learning Centre Answer to Chemistry Tuition Question on Redox Reactions. (O Level Chemistry Tuition/ IP Chemistry Tuition) 1.B 2.C 3.D Learn from our Chemistry Tuition Questions and Answers. Miracle Learning Centre Call 6463 8756 or sms 8128 8342/9839 9908. (Specialist in Science and Maths) for Primary, Secondary and JC levels. Miracle Learning Centre specialises in Chemistry tuition, Physics tuition, Maths tuition and Science tuition Classes.

Miracle Learning Centre Physics Tuition Question on Temperature. (O Level Physics Tuition / IP Physics Tuition)

1. The length of the mercury thread is found to be 6 cm and 20 cm at 0oC and 70oC respectively on an ungraduated thermometer. (a) State the temperature that correspond to a length of 10 cm.

Temperature = __________ State the length of the mercury thread that corresponds to the steam point.

Length = ___________

Miracle Learning Centre Answer to Physics Tuition Question on Temperature. (O Level Physics Tuition / IP Physics Tuition) 1 (a) 14 cm rep 70 oC 4 cm rep (70/14) x 4 = 20oC (b) 70 oC rep 14 cm 1000C rep (14/70)x 100 = 20 cm Length = 20 + 6 = 26 cm Learn from our Physics Tuition Questions and Answers. Miracle Learning Centre Call 6463 8756 or sms 8128 8342/9839 9908. (Specialist in Science and Maths) for Primary, Secondary and JC levels. Miracle Learning Centre specialises in Physics tuition, Chemistry tuition, Maths tuition and Science tuition Classes.

Miracle Learning Centre Maths Tuition Question on Trigonometry. (O Level Maths Tuition/IP Maths Tuition/Secondary Maths Tuition)

1. ACF is a vertical wall. The angle of depression of a boy at B from the top of the wall, A, is 63˚. Calculate (a) the distance between the boy and the foot of the wall, F, (b) the angle of elevation of a point C on the wall, 4 m above F, from the boy at B.

Miracle Learning Centre Answer to Maths Tuition Question on Trigonometry. (O Level Maths Tuition/IP Maths Tuition/Secondary Maths Tuition) 1.(a) BAF = 90˚ - 63˚ = 27˚ tan 27˚ = BF = 3.06 m (3sf) 1(b) tan CBF = CBF = 52.6˚ (1dp) Learn from our Maths Tuition Questions and Answers. Miracle Learning Centre Call 6463 8756 or sms 8128 8342/9839 9908. (Specialist in Science and Maths) for Primary, Secondary and JC levels. Miracle Learning Centre specialises in Maths tuition, Science tuition, Chemistry tuition and Physics tuition classes.

Separation Techniques - Chromatography

Chemistry tuition classes in Miracle Learning Centre is very useful. If you do not understand chemistry, you must definitely attend the chemistry tuition class at Miracle Learning Centre. Let us learn about separation techniques - chromatography in this chemistry tuition lesson.

Your chemistry tuition teacher at Miracle Learning Centre will teach you about chromatography. Chromatography is used to separate different dyes based on their relative solubility in the solvent. The more soluble dye to travel higher up the paper. The less soluble will be nearer to the starting line. The dyes are compared based on the Rf value. Rf value refers to the ratio of the distance travelled by the substance to the distance travelled by the solvent.

Chromatography is very useful in scientific research. The results can be obtained very quickly. The main advantage is that it requires a very small amount of the mixture. It is used to test for purity of a substance and to analyse drugs in urine samples. Chromatography can be used to analyse colourless substances as well. A locating agent will be sprayed on the chromatogram to react with the dye to form a coloured compound.

The student at Miracle Learning Centre asked, "What is the solvent commonly used in chromatography?" The chemistry tuition teacher at Miracle Learning Centre replied, "The solvent commonly used in chromatography is ethanol. Ethanol is a good solvent. The beaker needs to covered to prevent evaporation of the solvent. "

Miracle Learning Centre hope you have understood the chromatography and how it helps you to answer chemistry tuition questions. Do come to Miracle Learning Centre for more chemistry tuition lessons to learn more about chromatography and chemistry.