Gobezoch › Textbooks › Chemistry Grade 9
Chemistry Grade 9 Unit 2: MEASUREMENTS AND SCIENTIFIC METHODS
national exam questions have come from this unit. It runs 33 pages; one careful study pass takes about 4.5 hours, and its difficulty is easier among Chemistry units. Each section below lists the questions set from it, with the year, and opens the page that teaches it.
2.1 Measurements and Units in Chemistry · read p. 19
- 2016 E.C., Q5 – During summer, the average value for the temperature measured in a certain chemistry laboratory is 298.15 K. How many decimal places are there in the measured value?
- 2015 E.C., Q29 – The number of digits to the right of the decimal point denotes:
- 2015 E.C., Q43 – A student uses a digital balance (±0.02), a thermometer (±0.1), a measuring cylinder (±0.05), and a beaker (±0.5) during an experiment. Which of the above instrument is more precise?
- 2014 E.C., Q17 – Which of the following is a fundamental quantity SI unit?
- 2013 E.C., Q14 – One of the following is NOT a cause of uncertainty in measurement?
- 2013 E.C., Q11 – Significant figures are figures with
- 2012 E.C., Q68 – Which will be the best method to decrease the random uncertainty of a measurement in an acid-base titration?
- 2008 E.C., Q20 – Which of the following is correct?
- 2007 E.C., Q18 – Which of the following is correct?
- 2006 E.C., Q2 – Which of the following is correct?
- 2005 E.C., Q55 – What is the Kelvin scale (K) corresponding to the temperature readings when the degree Celsius ( ) is identical F 0 to the degree Fahrenheit ( )?
- 2005 E.C., Q16 – What is the number of significant figures in 0.0030050?
- 2005 E.C., Q47 – What is the quantity of heat required to raise the temperature of 80g of ethanol from to ? (specific 2.46 Jg K −1 −1 heat of ethanol = )
- 2005 E.C., Q1 – Which of the following is NOT a basic SI unit?
2.2 Chemistry as Experimental Science · read p. 36
- 2013 E.C., Q12 – For the determination of the density of a new ceramic, a student measured the mass of a piece on an analytical balance and obtained 3.8056 gram and its volume 2.5 mL by displacement of water in a graduated cylinder. The
- 2013 E.C., Q44 – The sanitizer in wide use for protection against Covid-19 is labelled 83% alcohol. How can one scientifically check the concentration?
- 2013 E.C., Q13 – The scientific method is
- 2012 E.C., Q57 – Which of the following data gives the most precise measurement?
- 2011 E.C., Q72 – What is the basis for the Scientific Method?
- 2011 E.C., Q18 – What is the first step in a scientific investigation?
- 2011 E.C., Q31 – Precision refers to _________
- 2010 E.C., Q55 – The determine the volume of an irregularly shaped glass vessel, the vessel is weighed empty ($121.3\text{g}$) and when filled with $\mathrm{CCl_4}$ ($283.2\text{g}$). What is the volume capacity of the vessel, given that
- 2010 E.C., Q12 – What is a measure of the closeness of a measurement to its true value?
- 2010 E.C., Q22 – What skill is a scientist using when he/she listens to the sounds that animals make?
- 2009 E.C., Q14 – Which of the following is NOT a laboratory safety rule?
- 2008 E.C., Q28 – In order to advance the level of a theory, a hypothesis should:
- 2008 E.C., Q5 – What is the first step of the scientific method?
- 2007 E.C., Q3 – The first step of the scientific method involves
- 2006 E.C., Q7 – A dot labelled 6 lies below the rising right-hand curve, beneath point 5.]
- 2005 E.C., Q61 – If a piece of aluminium (Al) foil measuring 24 cm by 31 cm has a mass of 10.35 g, (density of Al = $2.70\,\text{gcm}^{-3}$). What is the thickness of the foil in millimetres?