a) Define the following terms: i.Analysis ii.Confidence Interval (2 marks) b) State any three advantages of Instrumental Methods of analysis. (3 marks) c) How many significant figures do the following numbers have? 0.0050 ii. 9times 10^3 (2 marks) d) State the four types of determinate errors. (2 marks) e) Describe two ways in which a determinate error might occur while using a pipet to transfer a known volume of liquid. (2 marks)

Question

a) Define the following terms: i.Analysis ii.Confidence Interval (2 marks) b) State any three advantages of Instrumental Methods of analysis. (3 marks) c) How many significant figures do the following numbers have? 0.0050 ii. 9times 10^3 (2 marks) d) State the four types of determinate errors. (2 marks) e) Describe two ways in which a determinate error might occur while using a pipet to transfer a known volume of liquid. (2 marks)

Answer 1

a) Definitions:i. Analysis: Analysis refers to the process of breaking down a complex subject into its component parts to understand it better and to interpret the relationships between those parts. In scientific terms, it often involves examining the properties, composition, and structure of substances.ii. Confidence Interval: A confidence interval is a range of values, derived from sample statistics, that is likely to contain the value of an unknown population parameter. The interval has an associated confidence level that quantifies the level of confidence that the parameter lies within the interval.b) Three advantages of Instrumental Methods of analysis:1. Accuracy: Instrumental methods often provide highly accurate results compared to other methods.2. Speed: These methods can analyze samples quickly, which is crucial for timely decision-making.3. Sensitivity: Instrumental methods can detect very low levels of substances, making them ideal for environmental and clinical analyses.c) Significant figures:i. 0.0050: This number has two significant figures (5 and 0).ii.

: This number has one significant figure (9).d) Four types of determinate errors:1. Systematic errors: These are consistent, repeatable errors that occur due to a flaw in the measurement system.2. Random errors: These errors occur unpredictably and without a discernible pattern.3. Gross errors: These are large errors that result from human mistakes or equipment malfunctions.4. Environmental errors: These errors are caused by external factors such as temperature, humidity, or pressure.e) Two ways in which a determinate error might occur while using a pipet to transfer a known volume of liquid:1. Reading the meniscus at eye level: If the pipet is not held at eye level while reading the meniscus, the volume of liquid read may not be accurate.2. Not allowing the pipet to drain completely: If the pipet is not allowed to drain completely after filling with the liquid, the remaining volume in the pipet will be less than the intended volume, leading to a determinate error.

Question

Solution

Resposta