Reason1: electrons on farther layers become free easyer
2nd reason: volume of atoms grows (from Helium to Xeon) so instead of boyle-mariot law equation (PV=vRT) is more accurate to use van der walls equations that adds to the boyle-mariot equation the volume occupied by the atoms of the gas to the volume of the space between the atoms P(Vm-b)=vRT
Mercury (ii) oxide is made up of mercury and oxygen. The total mass of mercury (ii) oxide is 14.2 g, after decomposition 13.2 g of mercury were formed, therefore the mass of oxygen 1 g (14.2 g -13.2 g).
Percentage of oxygen = (1/14.2)×100 = 7.04%
Percentage of mercury = (13.2/14.2) × 100 = 92.96%
Therefore, percentage composition of the compound, oxygen is 7.04% and mercury is 92.96%.
The Chemistry Regents is one of the four science Regents exams. The other three are Earth Science, Living Environment, and Physics. You'll need to pass at least one of these four exams to graduate high school.
Answer:
The 197Au isotope has 79 protons, 79 electrons and 118 neutrons
Explanation:
Step 1: The isotope = 197Au
Step 2: Calculate neutrons, electrons and protons
197 = Number of protons + number of neutrons
Isotopes always have the same proton number ( is the same as the atomic number). For Gold (Au) is this 79.
The number of electrons is equal to the number of protons in a neutral atom. Since we have 79 protons, there are also 79 electrons.
All isotopes of Au have a different number of neutrons.
The number of neutrons = 197 -79 = 118 neutrons
The 197Au isotope has 79 protons, 79 electrons and 118 neutrons
