Chemistry Practical Package - Experimental Techniques & Qualitative Analysis

Flashcards covering laboratory apparatus precision, titration techniques, qualitative analysis tests for ions and gases, and experimental data presentation based on the TKGS Chemistry Practical Package.

When measuring the volume of a liquid using a measuring cylinder, you must align your eyes to the liquid level and read the scale at the __________ of the meniscus.

bottom

When determining the mass of a solid in a test-tube using an electronic balance, you should place the test-tube in a __________ and press Tare first.

beaker

A burette has a smallest division of $0.1\,\text{cm}^3$ and an uncertainty of __________ .

$$0.05\,\text{cm}^3$$

The volume of a pipette is typically recorded to __________ decimal place.

$$1$$

In a graph where you are asked to 'Plot A against B', the variable A is plotted on the __________ .

$y$-axis

A graph unit represents a unit of $1$, $10$, $20$, $100$, or __________ for good scaling.

$$0.1$$

To account for human reaction time when using a stopwatch, the best procedure is repeating the readings and obtaining the __________ reading.

average

To reduce heat loss to the surroundings during a temperature change experiment, you should use a __________ cup.

Styrofoam

When preparing for titration, the burette should be rinsed with tap water, distilled water, and then the __________ .

given solution

A conical flask used in titration should only be rinsed with tap water and __________ .

distilled water

For opaque solutions like potassium manganate(VII), the volume reading from a burette is taken from the __________ of the meniscus.

top

In an acid-base titration where acid is added to an alkali, Screened Methyl Orange turns from green to __________ at the end point.

Grey

Thymolphthalein indicator is __________ in an acidic solution after the end point.

Colourless

To determine the average volume used in a titration, you should use the best two results that are within __________ of each other.

$$\pm 0.10\,\text{cm}^3$$

In Qualitative Analysis, the test for carbonate ($CO_3^{2-}$) ions involves adding dilute acid and testing the resulting gas with __________ .

limewater

When testing for nitrate ($NO_3^-$) ions, you add aqueous sodium hydroxide and __________ , then warm carefully to produce ammonia gas.

aluminium foil

To test for iodide ($I^-$) ions, you acidify the solution with nitric acid and then add aqueous __________ .

silver nitrate

Copper(II) ($Cu^{2+}$) ions produce a light blue precipitate when aqueous ammonia is added, which is soluble in excess to give a __________ solution.

dark blue

The test for sulfur dioxide ($SO_2$) gas involves placing a filter paper moistened with acidified __________ at the mouth of the test-tube.

potassium manganate(VII)

Chlorine ($Cl_2$) gas is a greenish-yellow gas with a pungent smell that turns moist blue litmus paper red and then __________ it.

bleaches

In the reactivity series, a metal that releases more energy when displacing copper from copper(II) sulfate is considered __________ reactive.

more

In investigative planning, the variable that undergoes changes due to changes in another variable and is usually measured is the __________ variable.

dependent