C ( Porcupines use there’s sharp quills to defend themselves from larger predators!)
Answer:
More energy is released from the old substance than the new substance needs to form its chemical bonds
Explanation:
Edge 2020
A) Cu
Cu + 2HCl --> CuCl2 + H2(g)
Products predicted: Copper(II) choloride and hydrogen gas
B) Mg
Mg + 2HCl --> MgCl2 + H2
Products predicted: magnesium chloride + hygrogen gas
C) Fe
Fe +2 HCl -> FeCl2 + H2, or
2Fe +6 HCl -> 2FeCl3 + 3H2
Products predicted: Iron(II) chloride, iron (III) chloride and hydrogen gas.
The HCl added = 1.25 moles
and the moles of Na2HPO4 = 1 mole
Now when acid is added in the given solution of Na2HPO4
One mole of H+ will react with one mole of Na2HPO4 to given one mole of NaH2PO4
Na2HPO4 + H+ ---> NaH2PO4
Now this one mole formed NaH2PO4 will further react with 0.25 moles of H+ left to form 0.25 moles of H3PO4 and 0.75 moles of NaH2PO4 will remain in the solution
So this will result into formation of a buffer of phosphoric acid and NaH2PO4
NaH2PO4 + H+ ---> H3PO4
pKa of H3PO4 = 2.1
so pH = pKa + log [salt] / [acid] = 2.1 + log [0.75 / 0.25] = 2.58
so the pH will be in between 2.1 to 7.2
Answer:
Molecular compounds are pure substances formed when atoms are linked together by sharing of electrons while ionic compounds are formed due to the transfer of electrons.
Molecular compounds are made due to covalent bonding while ionic compounds are made due to ionic bonding.
Explanation: