Answer:
Element; compound
Explanation:
Oxygen is an element on the periodic table, but when it's combined with the element Hydrogen, it produces water, which is a compound (H2O). When two elements combine, it produces a compound.
I hope this helps! :)
From the given pH, we calculate the concentration of H+:
[H+] = 10^-pH = 10^-5.5
We then use the volume to solve for the number of moles of H+:
moles H+ = 10^-5.5M * 4.3x10^9 L = 13598 moles
From the balanced equation of the neutralization of hydrogen ion by limestone written as
CaCO3(s) + 2H+(aq) → Ca2+(aq) + H2CO3(aq)
we use the mole ratio of limestone CaCO3 and H+ from their coefficients, which is 1 mole of CaCO3 is to react with 2 moles of H+, to compute for the mass of the limestone:
mass CaCO3 = 13598mol H+(1mol CaCO3/2mol H+)
(100.0869g CaCO3/1mol CaCO3)(1kg/1000g)
= 680 kg
- Endothermic reaction means the reactant side takes heat from surrounding and get decomposed i.e ∆H=-ve
- If the equation is exothermic then it means the reactant is happy to decompose .But it's not as it's endothermic
Now
- HgO is Omitted from our solution option.
Hg is a atom so no bonds hence no bond strength occurs.
- O_2 is a molecule and so it's our answer .
That is correct hope that helps
