Basic analytical chemistry UE Past Papers Questions.

The of hypochlorous acid (HClO) is at 25°C. What is the % ionization of hypochlorous acid in a 0.015 M aqueous solution of HClO at 25°C?

2. 14
5. 0.14

Answer / Solution

UNSOLVED

The for formic acid is What is the pH of a 0.35M aqueous solution of sodium formate?

1. 5.36
2. 8.64
3. 10.71
4. 4.20
5. 3.29

Answer / Solution

UNSOLVED

Four different CHE 101 students perform the calculation , 451.0g-15.46g and came up with answers given below. Which answer was the most acurate.

1. 436g
2. 435.54g
3. 435g
4. 435.5g

Answer / Solution

UNSOLVED

Which experimental technique reduces the systematic error in the investigation?

1. Using a magnifying glass to enlarge the meniscus in a burette
2. Repeating a titration a number of times and calculating an average titre.
3. Using a larger amount of an indicator during a titration.
4. Adjusting an electronic balance to remove its zero error before weighing a chemical.
5. When comparing systematic errors and random uncertainties during an investigation, the following properties of errors in an experimental measurement may be considered :

1. Error can possibly be removed
2. Error cannot possibly be removed
3. Error is of constant sign and size
4. Error is of varying sign and size
5. Error will be reduced by averaging repeated measurements
6. Error will not be reduced by averaging repeated measurements

Which properties apply to random uncertainties?

1. I,II,III
2. I,IV,VI
3. II,IV,V
4. II,III,V

Answer / Solution

UNSOLVED