C8

Question 1

what is a pure substance?
what does boiling or melting point tell you?
how can you test the purity of a sample?
the closer your measured value……?

Answer 1

-Pure substance is something that only contains one compound or element throughout not mixed with anything
-Pure substance will melt or boil at a specific temperature
-You can the test the purity of a sample by measuring its boiling and melting point and comparing it to the melting or boiling point of the pure substance (data book)
-The closer your measured value is to the actual melting or boiling point the purer your sample

Question 2

what does impurities in sample do?
what are formulations?

Answer 2

-Impurities in your sample will lower the melting point and increase the melting range of your substance.But it will increase the boiling point
-Formulations are useful mixtures with a precise purpose that are made following a formula.They
are made by mixing the components in carefully measured quantities to ensure
that the product has the required properties.

Question 3

why are formulations important in pharmaceutical industry?
where can formulations be found in everyday products?
on a product what does ratio or percentage tell you?

Answer 3

Important in the pharmaceutical industry for eg altering the formulations of a pill chemists can make sure it delivers the drug to the correct part of the body at the right concentration
-They can be found in cleaning products,metal alloys,fuels,cosmetics,fuels and even food and drink
-The ratio or the percentage tell you each component.This tell you the product is a formualtion

Question 4

what are the tests for 4 common gases?

Answer 4

1) Chlorine-Chlorine bleaches damp litmus paper it turns white (it turns red for a moment first though because its a solution of chlorine which is acidic
2)Oxygen-If you put a glowing splint inside a test tube containing oxygen the oxygen will relight the glowing splint
3)Carbon dioxide-Bubbling carbon dioxide through or shaking carbon dioxide with an aqueous solution of calcium hydroxide (known as limewater) causes the solution to turn cloudy
4)Hydrogen-if you hold a lit splint at the end of an open test containing hydrogen you’ll get a squeaky pop.(noises come from the hydrogen burning quickly with the oxygen in the air to form H20