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0.120g of an ideal gas was introduced into a gas syringe. The volume occupied by the gas at a pressure of 1.02x10^5 Pa and temperature 20 degrees was 49.3 cm^3. Calculate the molar mass of the gas.

The ideal gas law is PV=nRT, and we know that we can achieve the molar mass through the relationship of; n=m/mr. When using the ideal gas law it is essential that we use SI units before we begin plugging ...

Answered by Robbie S. • Chemistry tutor

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How would you synthesise an carboxylic acid just from a primary haloalkane like bromoethane?

Nucleophilic substitution using NaOH to convert haloalkane to primary alcohol. This is a mechanism that you need to know for the exam. Then oxidise the alcohol by refluxing with acidified potassium dichro...

Answered by Ollie W. • Chemistry tutor

4517 Views

What are the half equations representing the changes of Pb2+ and Br- in the electrolysis of lead bromide?

Pb2+ + 2e- -> Pb 2Br- -> Br2 + 2e- Lead ions undergo reduction (gain of electrons) at the negative electrode to form solid lead. Bromide ions undergo oxidation (loss of electrons) at the positive el...

Answered by Sophie F. • Chemistry tutor

40376 Views

What observations would I expect to make if I dropped from magnesium into some hydrochloric acid? What is the balanced chemical equation?

Effervescence and the magnesium metal would dissolve. Mg + 2HCl --> MgCl2 + H2

Answered by Ollie W. • Chemistry tutor

3715 Views

What is the difference between an acid and a base?

An acid when dissolved in a liquid, will produce hydrogen ions (H+) while a base will produce hydroxide ions (OH-). When a litmus paper is used to test acids and bases, acids turn the litmus paper red whi...

Answered by Laudina S. • Chemistry tutor

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