Answer:
Mass = 112 g
Explanation:
Given data:
Mass of CO₂ produced = 90.6 g
Mass of oxygen needed = ?
Solution:
Chemical equation:
C₃H₈ + 5O₂ → 3CO₂+ 4H₂O
Number of moles of CO₂:
Number of moles = 90.6 g/ 44 g/mol
Number of moles = 2.1 mol
Now we will compare the moles of CO₂ and oxygen:
CO₂ : O₂
3 : 5
2.1 : 5/3×2.1 = 3.5
Mass of oxygen needed:
Mass = number of moles × molar mass
Mass = 3.5 mol × 32 g/mol
Mass = 112 g
Answer:
See Explanation
Explanation:
Metallic bonds involve attraction between electrons and positively charged metal ions. The metals are ionized and electrons form a sea of valence electrons. These loosely bound electrons surround the nuclei of the metals.
The presence of this sea of electrons explains the fact that metals conduct electricity and heat due to the free valence electrons.
Due to the nature of the bonding between metal atoms,metals are malleable and ductile.
Due to the strong electrostatic interaction between metal ions and electrons, the metallic bond is very strong and is very difficult to break thereby accounting for the greater strength of metals as the size of the metallic ion decreases.
For better representation, let me rewrite the electronic configuration:
<span>1s</span>²<span>2s</span>²<span>2p</span>⁶<span>3s</span>²<span>3p</span>⁶<span>4s</span>²<span>3d</span>⁴
The exponents represent the number of electrons in the designated subshell. Thus, the total number of electrons are:
# of electrons = 2+2+6+2+6+2+4 = 24
Assuming this is in neutral state, the element with an atomic number of 24 is Chromium. Thus, the answer is Cr.
Answer:
Carbon, germanium, tin and lead.
Explanation:
The silicon is belong to the carbon family. There are five elements in carbon family carbon, silicon, germanium, tin and lead. These five elements are present in same group i.e group fourteen. The elements present in same group have same number of valance electrons.
For example.
Carbon electronic configuration:
C₆ = [He] 2s² 2p²
Silicon electronic configuration:
Si₁₄ = [Ne] 3s² 3p²
Germanium electronic configuration:
Ge₃₂ = [Ar] 3d¹⁰ 4s² 4p²
Tin electronic configuration:
Sn₅₀ = [Kr] 4d¹⁰ 5s² 5p²
Lead electronic configuration:
Pb₈₂ = [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p²
we can see that in case of all elements there are four valance electrons, which are equal to the valance electrons of silicon.
