Measurments In Chemistry Flashcards
What is the s i unit for measuring volume and what are some instruments to measure volume?
The s i unit for measuring volume is Cubic metre
Small volumes are measured in cubic centimetre
Where are the large volumes are measured in cubic decimeter
A beaker and conical flask can hold approximate volumes of 200 cm cube
What is the accuracy of measuring cylinder?
Approximately measure the volume of a liquid to the nearest 0.5 CM
Example 24 cm cube or 32.5cm³
What is the accuracy of a burette?
Accurately measures the volume of a liquid to the nearest 0.05 centimetre
For example 23.00 CM 34.45 CM³
What is the accuracy of a pippete ?
Accurately measure with a fixed volume
Of liquid
Example 24 cm cube A 25 cm cube
What are the usual laboratory thermometer?
The usual laboratory thermometer is mercury in glass or alcohol in glass type
What is the s i unit of Temperature?
Laser unit with temperature is Kelvin
What is the difference between kelvin and Celsius?
Temperature in kelvin is equal to temperature in Celsius plus 273.
What is the lowest temperature theoretically possible on the Kelvin scale?
Lowest temperature possible on Kelvin scale is zero degrees which is equal to minus 273 degrees which is known as absolute zero.
What is the SI unit for time?
Measured in hours minutes seconds
What is Mass?
Is the measurement of the amount of matter contained in a body.
What is the SI unit for mass?
Mass is measured in kilograms smaller masses are measured in grams
What two types of instruments are used to measure masses in chemistry?
Triple beam balance and an electronic top balance.
To what accuracy does a triple beam balance measure up to.
It was up to 0.1 gram
What accuracy does a electronic top Pan balance measure to?
It measures to the nearest 0.001g
When is displacement of Water used for the collection of gases?
It is used to collect the gases that are insoluble or slightly soluble in water for example hydrogen carbon dioxide and oxygen.
When is downwards delivery used to collect gas?
This is used for the collection of gases that are soluble in water and more dense than air for example chlorine.
When is upward delivery used for the collection of gases
It is used when the gases are soluble in water and is less dense than air. For example Ammonia and hydrogen
Why would you use a gas change to collect gas?
this is particularly useful when you want to collect and measure the volume of gas over a period of time gas produced from the reaction of a substance in the conical flask is collected in the gas syringe the Apparatus is useful in experiments on speed of reaction.
