Answer: 6
Explanation: if you multiply the number of moles in the hydrogen atoms by the number of the once displayed and you multiply it by 3 and get the answer 6
atomic mass=percentage of isotope a * mass of isotope a + percentage of isotope b * mass of isotope b+...+percentage of isotope n * mass of isotope n.
Data:
mass of isotope₁=267.8 u
percentage of isotope₁=90.3%
mass of isotope₂=270.9 u
percentage of isotope₂=9.7%
Therefore:
atomic mass=(0.903)(267.8 u)+(0.097)(270.9 u)=
=241.8234 u + 26.2773 u≈268.1 u
Answer: the mass atomic of this element would be 268.1 u
Across a period I.E increases progressively from left to right
Explanation:
The trend of the first ionization energy is such that across a period I.E increases from left to right due to the decreasing atomic radii caused by the increasing nuclear charge. This not compensated for by successive electronic shells.
- Ionization energy is a measure of the readiness of an atom to lose an electron.
- The lower the value, the easier it is for an atom to lose an electron.
- Elements in group I tend to lose their electrons more readily whereas the halogens hold most tightly to them.
- The first ionization energy is the energy needed to remove the most loosely bonded electron of an atom in the gaseous phase.
Learn more:
Ionization energy brainly.com/question/6324347
#learnwithBrainly
Answer:
O2, oxygen.
Explanation:
Hello.
In this case, for the undergoing chemical reaction, we need to compute the moles of CO2 yielded by 85 g of CH4 (molar mass = 16 g/mol) and by 320 g of O2 (molar mass 32 g/mol) via the following mole-mass relationships:

Considering the 1:2:1 among CH4, O2 and CO2. Therefore, since 320 g of O2 yield the smallest amount of CO2 we infer that the limiting reactant is O2.
Best regards.