Answer:
B. A chemist
<em>Hope it's help :)</em>
Answer:
-179.06 kJ
Explanation:
Let's consider the following balanced reaction.
HCl(g) + NaOH(s) ⟶ NaCl(s) + H₂O(l)
We can calculate the standard enthalpy change for the reaction (ΔH°r) using the following expression.
ΔH°r = 1 mol × ΔH°f(NaCl(s)) + 1 mol × ΔH°f(H₂O(l)) - 1 mol × ΔH°f(HCl(g)) - 1 mol × ΔH°f(NaOH(s))
ΔH°r = 1 mol × (-411.15 kJ/mol) + 1 mol × (-285.83 kJ/mol) - 1 mol × (-92.31 kJ/mol) - 1 mol × (-425.61 kJ/mol)
ΔH°r = -179.06 kJ
7.30 x 10^-7 km. the others have 4 significant figures.
Answer:
3.8 x 10²⁴molecules
Explanation:
Given parameters:
Number of moles = 6.32moles
Unknown:
Number of molecules = ?
Solution:
The number of moles can be used to derive the number of molecules found within a substance.
Now,
1 mole of substance contains 6.02 x 10²³ molecules
6.32 mole of PBr₃ will contain 6.32 x 6.02 x 10²³ = 3.8 x 10²⁴molecules
