The scientific notation of 420,000 is : 4.2 x 10 ^ 5
Answer: It passes through both mantle and core, but are slowed and refracted at the mantle / core boundary at a depth of 2900 km.
Explanation:
Answer:
It would get <u>colder</u>
Explanation:
The lattice energy is the energy involved in the disruption of interactions between the ions of the salt. In this case, we have: ΔHlat = 350 kJ/mol > 0, so it is an endothermic process (the energy is absorbed).
The solvation energy is the energy involved in forming interactions between water molecules and the ions of the salt. In this case, we have: ΔHsolv = 320 kJ/mol > 0, so it is an endothermic process (the energy is absorbed).
The dissolution process involve both processes: the disruption of ion-ion interactions of the salt and the solvation process. Thus, the enthalphy change (ΔHsol) in the preparation of the solution is calculated as the addition of the lattice energy and solvation energy:
ΔHsol= ΔHlat + ΔHsolv = 350 kJ/mol + 320 kJ/mol = 370 kJ/mol
370 kJ/mol > 0 ⇒ endothermic process
Since the preparation of the solution is an <u>endothermic</u> process, it will absorb energy from the surroundings, so <u>the solution would get colder</u>.
Ba(OH)2 is an basic solution. It has more OH- ions than H+ ions. pOH should be calculated to find out its pH
The reaction is
Ba(OH)2 ⇒ Ba2+ (aq) + 2 OH-(aq)
One mole barium hydroxide releases 2 moles hydroxide ions.
Use that ratio to calculate molarity (M) of OH- ions [OH-]. The ratio is 1:2.
0.10 M Ba(OH)2 release 2*0.10 M= 0.02 M OH- ions
[OH-]= 0.02
pOH= - log [OH-] = - log 0.02 = 1.7
Thats not the answer! We found pOH of the solution before titration.
pH and pOH relationship is shown by formula of pH+pOH= 14
pH= 14-pOH
pH= 14-1.7= 12.3
