This material has a density of 1 g/cm3.
(since 12.48 g/ 12.48 cm3 = 1 g/cm3)
Therefore, this material is water.
Covalent bonds form when atoms share electrons. This sharing allows each atom to achieve its octet of electrons and greater stability. Methane, CH 4<span>, the simplest organic compound, contains covalent bonds. Carbon has four valence electrons, while hydrogen has one valence electron. By sharing these outer‐shell electrons, carbon and hydrogen complete their valence shells and become more stable. The duet of electrons on the hydrogen is isoelectronic with helium and forms a complete shell.</span>
Answer:
Option B.
Explanation:
As any reaction of combustion, the O₂ is a reactant and the products are CO₂ and H₂O. Combustion reaction for ethane is:
2C₂H₆ + 7O₂ → 4CO₂ + 6H₂O
So 2 moles of ethane react with 7 moles of oxygen to make 4 moles of dioxide and 6 moles of water.
Then 2 moles of ethane will produce 4 moles of CO₂
Answer:
400°C
Explanation:
22,000 cal / (0.11 cal/g°C x 500 g) = 400°C
Electrons in an atom can be classified as core electrons and valence electrons. Valence electrons are those electrons which are present in valence shell and participates in bond formation. While, Core electrons are all remaining electrons which are not present in valence shell, hence not take part in bonding.
Atomic number of Selenium (Se) is 34 hence it has 34 electrons with following electronic configuration;
1s², 2s², 2p⁶, 3s², 3p⁶, 4s², 3d¹⁰, 4p⁴
From electronic configuration it is found that the valence shell is 4, and the number of electrons present in valence shell are 6. So,
Core Electrons = Total Electrons - Valence Electrons
Core Electrons = 34 - 6
Core Electrons = 28
Result:
There are 28 core electrons in Selenium.