Just post the question on here
1) is chemical Bonds
3) Conservation of mass
5) compound
hope i helped on the ones i could answer
You first need to write the balanced chemical reaction for what is going on.
Ca(OH)₂+2HCl→2H₂O+CaCl₂
After you make the balanced chemical reaction, First you find the moles of HCl used. To do this multiply 0.0375L by 0.124M to get 0.00465mol HCl. Then you multiply 0.00465mol HCl by (1mol Ca(OH)₂)/(2mol HCl) to get 0.002325mol Ca(OH)₂. Finally to find concentration of Ca(OH)₂ used you divide 0.002325mol by 0.020L to get 0.116M Ca(OH)₂.
Therefore the concentration of the unknown solution of Ca(OH)₂ was 0.116M.
I hope this helps. Let me know if anything is unclear.
<span>The correct answers are A, B, and D. The ΔHrxn is equal to the ΔHf when the ΔHf of the reactants is zero, and this can only occur when the reactants are pure elements (not compounds) in their natural phase at ambient temperature.
c) Chlorine's natural phase is gaseous, but since it is a liquid in this reaction, ΔHf ≠ 0.
e) CO is a compound, not a pure element.
f) BaCO3 is a compound, not a pure element.</span>
The most basic level of organization that is involved in converting fuel or food into forms of energy, are found and compose living things. These are called cells.