Test your knowledge and answer these for me (1 Viewer)

Blake Henderson

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A) If an aquarium tank holds 70 litres of water, calculate how much heat energy would be required to heat the tank from 18.2 degrees celcius to 26.5 degrees celcius. Note the density of water is known to be 1g/mL.


B) sucrose is a covalent molecular compound that dissolves in water to produce a solution that does not conduct electricity. Hydrogen chloride is also a covalent molecular compound that dissolves in water to producr a solution that does conduct electricity. Explain why this occurs.


C) with reference to molecular forces, explain why more energy is required to produce hydrogen from water than to produce steam frlm water.


D) you have performed a first-hand investigation of the reactions of a range of metals with dilute acie. Choose a metal which reacts more slowly than magnesium but more rapidly than lead to answer following questions: A) describe youe procedure and the observations you made. B) identify the products of the reaction, by name and formula.

Write A), B), C), D) a) b) before the answers
 

Blake Henderson

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E) potassium has electron configuration of 2,8,8,1 and sulfur has the electron configuration 2,8,6
a) write half equations for each, showing how the ions of each of the elements are formed.
b) identify the product formed when potassium reacts with sulfur to form an ionic compound and write its formula
c) predict the formula for the compound formed between sulfur and oxygen ans identify the bonding present in the compound


F) write balanced equations, showing states, for:
a) phosphorus (s) burns in air to produce a white powder, diphosphorus trioxide
b) dilute sulfuric acid causes insoluble copper carbonate to dissolve, forming copper sulfate and carbon dioxide gas and water.


Am marking answers
 

fatassmcfat

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Did first half then realised this is year 11 stuff
A) 2428.58 Joules (tell me if its right)
B) not sure, something to do with only ionic stuff can conduct electricity because the free ions flow around but covalents are like stuck together
C) ELECTROLYSIS: 2H2O (l) --> 2H2(g) + O2 (g) requires breaking the very strong hydrogen bond in water. Whilst converting to STEAM 2H2O (l) --> 2H2O (g) is only a physical transition i.e. you heat it up past boiling point
D) I dont even remember this prac (but im in yr 12)!

Hope it helps a bit
 

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