Answer:
Each principal energy level above the first contains one s orbital and three p orbitals. A set of three p orbitals, called the p sublevel, can hold a maximum of six electrons. Therefore, the second level can contain a maximum of eight electrons - that is, two in the s orbital and 6 in the three p orbitals.
Explanation:
Answer:
only columns
Explanation:
All atoms of elements present in same group or column having same number of valance electrons. Thus the elements in same group having same properties.
For example:
Consider the second group. It consist of alkaline earth metals. There are six elements in second group. Beryllium, magnesium, calcium, strontium, barium and radium.
All have two valance electrons.
Electronic configuration of Beryllium:
Be = [He] 2s²
Electronic configuration of magnesium.
Mg = [Ne] 3s²
Electronic configuration of calcium.
Ca = [Ar] 4s²
Electronic configuration of strontium.
Sr = [Kr] 5s²
Electronic configuration of barium.
Ba = [Xe] 6s²
Electronic configuration of radium.
Ra = [ Rn] 7s²
They are present in group two and have same number of valance electrons (two valance electrons) and show similar reactivity.
They react with oxygen and form oxide.
2Ba + O₂ → 2BaO
2Mg + O₂ → 2MgO
2Ca + O₂ → 2CaO
this oxide form hydroxide when react with water,
BaO + H₂O → Ba(OH)₂
MgO + H₂O → Mg(OH)₂
CaO + H₂O → Ca(OH)₂
With sulfur,
Mg + S → MgS
Ca + S → CaS
Ba + S → BaS
1. Calculate no. of moles by dividing mass given/molar mass
= 0.250 /283.8
2. Now multiply no. of moles with avogadro's no.
3. The answer indicates no. of total atoms..
1) developing country
2) Mitochondria
3) developed country
4) metabolic process
5) cellular respiration
6) poverty
7) overpopulation
8) standard of living
Answer:
P₂ = 3.19 atm
Explanation:
Given data:
Initial volume = 700 mL
Initial pressure = 1 atm
Initial temperature = 273K
Final temperature =100°C (100+273= 373 K)
Final volume = 300 mL
Final pressure = ?
Formula:
P₁V₁/T₁ = P₂V₂/T₂
P₁ = Initial pressure
V₁ = Initial volume
T₁ = Initial temperature
P₂ = Final pressure
V₂ = Final volume
T₂ = Final temperature
Solution:
P₂ = P₁V₁ T₂/ T₁ V₂
P₂ = 1 atm × 700 mL × 373K / 273 K ×300 mL
P₂ = 261100 atm .mL. K /81900 K .mL
P₂ = 3.19 atm
