It's an ionic bond! Potassium is a cation, or a metal with a positive charge, and fluoride is an anion, or a nonmetal with a negative charge.
A covalent bond is the bond between two nonmetals.
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Answer:

Explanation:
Hello,
In this case, the enthalpy of combustion is understood as the energy released when one mole of fuel, in this case octene, is burned in the presence of oxygen and is computed with the enthalpies of formation of the fuel, carbon dioxide and water as shown below (oxygen is circumvented as it is a pure element):

Thus, since we already know the enthalpy of combustion of the fuel, for carbon and water we have -393.5 and -241.8 kJ/mol respectively, thereby, the enthalpy of combustion turns out:

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this is a dilution question where a certain volume is taken from a more concentrated solution and diluted to make a solution with a lower concentration.
the dilution forumla is as follows
c1v1 = c2v2
where c1 is concentration and v1 is volume of the more concetrated solution
c2 is concentration and v2 is volume of the diluted solution
substituting the values in the equation
18.0 M x V = 0.126 M x 16.5 L
V = 0.1155 L
volume of 115.5 mL is taken from the 18.0 M solution and diluted upto 16.5 L solution.
<span>Answer:
The dilution formula is V1M1 = V2M2.
We need 3 of the values to calculate the 4th.
We have the original volume (2 mL of copper ion solution) and the final volume (20 mL), but we don't have the concentration of either the original or the final copper solution,
All we can say is the resulting solution is 10 times as dilute as the original was-
V1M1 = V2M2
2Ă—0.200 = 20Ă—M2, so M2 = 0.400/20 = 0.020M</span>