Answer:
1384 kJ/mol
Explanation:
The heat absorbed by the calorimeter is equal to the heat released due to the combustion of the organic compound. C is the total heat capacity of the calorimeter and Δt is the change in temperature from intial to final:
Q = CΔt = (3576 J°C⁻¹)(30.589°C - 25.000°C) = 19986.264 J
Extra significant figures are kept to avoid round-off errors.
We then calculate the moles of the organic compound:
(0.6654 g)(mol/46.07) = 0.0144432 mol
We then calculate the heat released per mole and convert to the proper units. (The conversion between kJ and J is infinitely precise and is not involved in the consideration of significant figures)
(19986.264 J)(1kJ/1000J) / (0.0144432 mol) = 1384 kJ/mol
Answer:
1st page, number a-ENergy is added or absorbed
I cant see the answers on the 2nd page
Explanation:
Since the barium ion will be isoelectronic to the nearest noble gas, which is xenon, the electronic configuration for Ba2+ is: [Xe]
Answer:
Option B is correct.
4
Explanation:
We know that an atom consist of electron, protons and neutrons. Protons and neutrons are present with in nucleus while the electrons are present out side the nucleus.
All these three subatomic particles construct an atom. A neutral atom have equal number of proton and electron. In other words we can say that negative and positive charges are equal in magnitude and cancel the each other. For example, if neutral atom has 6 protons than it must have 6 electrons. The sum of neutrons and protons is the mass number of an atom while the number of protons are number of electrons is the atomic number of an atom.
In given problem we are given with 2 neutrons of helium. We know that the atomic number of He is 2. Thus Mass number of He is,
Number of neutrons + number of proton
2 + 2 = 4
Thus, option B is correct.
