Answer:
Because density is mass divided by volume and it will always stay the same for a certain substance while mass and volume will always vary.
Answer:
CH4
Explanation:
In solving this problem, we must remember that one mole of a compound contains Avogadro's number of elementary entities. These elementary entities include atoms, molecules, ions etc. Recall that one mole of a substance is the amount of substance that contains the same number of elementary entities as 12g of carbon-12. The Avogadro's number is 6.02 × 10^23.
Hence we can now say;
If 163 g of the compound contains 6.13 ×10^24 molecules
x g will contain 6.02 × 10^23 molecules
x= 163 × 6.02 × 10^23 / 6.13 × 10^24
x= 981.26 × 10^23/ 6.13 ×10^24
x= 160.1 × 10^-1 g
x= 16.01 g
x= 16 g(approximately)
16 g is the molecular mass of methane hence x must be methane (CH4)
Answer:
Hydrogen
Explanation:
Hydrogen, most abundant in the universe, is the chemical element with atomic number 1, and an atomic mass of 1.00794 amu, the lightest of all known elements. It exists as a diatomic gas (H2).
Answer:
The exceptions to the periodic trends in ionization energy are the first ionization energy of beryllium is higher than that of boron and the first ionization energy of nitrogen is also higher than that of oxygen.
Explanation:
Taking a close look at the figure of first ionization energies, it clearly shows that the first ionization energy of beryllium is higher than that of boron and the first ionization energy of nitrogen is also higher than that of oxygen.
This is as a result of Hund's rule and electron configuration. For example, the first ionization potential electron of beryllium is obtained from a 2s orbital while that of boron comes from a 2p electron. However, for oxygen and nitrogen, their electrons are obtained from 2p orbitals. While spin is uniform for all 2p electrons of nitrogen, it is different for oxygen.
