TMA1/CHM192

My TMA Home TMA Results My Pending TMA Quick Help TMA Quiz Questions TMA: TMA1/CHM192 Matric Number:  SCORE=10.00  september 2016 CHM192 - Introductory Chemistry Practical II Miss Abdul Modupe (mabdul@noun.edu.ng ) 1 Which of the following is not a laboratory safety rule? You should never mix acids with bases You should tie back your long hair You should never add water to acid You should never pour chemicals down the sink 2 Which piece of laboratory equipment can be used to store chemicals for a long period of time? Burrette Evaporating dish Beaker Pippette 3 Which of these is not a correct use of the bunsen burner? Turn off the gas valve after use When not using the bunsen burner for a while, open the air-hole Never leave the flame unattended Open the air hole slowly 4 Which of the following can cause error during weighing? Presence of air currents in the lab Balance door being open Non-equilibration of balance All of the above 5 If you weighed a cold object on the balance, the reading would be _____________. Higher Lower Same None of the above 6 During the same experiment, one must be careful to always use _____________balance. Different Same Various None of the above 7 Which of these is not a component of the bunsen burner? Tong Chimney Air vent Needle valve 8 If a procedure tells you to "add about 3 g of ammonium sulphate", which balance would you use? Analytical balance Top-loading balance Spring balance All of the above 9 Which of these is more suitable for accurate measurement of mass? Spring balance Top-loading balance Analytical balance None of the above 10 Which of these is not a use of the bunsen burner? Sterilization combustion Heating Measuring 11 ____________ is the temperature at which the vapour pressure of a liquid equals atmospheric pressure. Absolute point Boiling point Normal boiling point All of the above 12 If you weighed a hot object on the balance, the reading would be _____________. Same Higher Lower None of the above 13 Solids are usually purified by the method of ____________. fractional distillation  distillation crystallization All of the above 14 Which of these helps you to keep solutions at a constant temperature while stirring? Magnetic stirrer Hot plate stirrer Mechanical stirrer Stirrer motor 15 What is the maximum capacity of the analytical balance? 110 g 210 g 620 g None of the above 16 What would you use to achieve a constant stirring? Magnetic stirrer Hot plate stirrer Mechanical stirrer Stirrer motor 17 What is the product formed when you dehydrate an alcohol? Alkene Alkane Alkyne Ester 18 What is the mole fraction of each component if 3.9 g of benzene (C6H6)$$(C_6{H}_6)$$ is dissolved in 4.6 g of toluene (C7H8)$$(C_7{H}_8)$$ ? 0.50 each 0.10 each 0.05 each 0.01 each 19 The maximum capacity of the top-loading machine is ____________. 620 g 210 g 110 g None of the above 20 ____________ is used to hold flasks and crucibles when they are hot. Bunsen burner Spatula Tong Holder