Ans: Elements in the same period have the same number of electron shells.
The molar mass of sodium is 22.99 ㅤ ㅤ ㅤ 22.99 (28) = 643.72 mol now multiply by avogrados number to find the number of atoms. ㅤ ㅤ ㅤ 643.72 (6.022 x 10^23) = 3.88 x 10^26 number of atoms
Balance Chemical Equation for combustion of Propane is as follow,
C₃H₈ + 5 O₂ → 3 CO₂ + 4 H₂O
According to equation,
1 mole of C₃H₈ on combustion gives = 4 moles of H₂O
So,
5 moles of C₃H₈ on combustion will give = X moles of H₂O
Solving for X,
X = (5 mol × 4 mol) ÷ 1 mole
X = 20 moles of H₂O
Calculating number of molecules for 20 moles of H₂O,
As,
1 mole of H₂O contains = 6.022 × 10²³ molecules
So,
20 moles of H₂O will contain = X molecules
Solving for X,
X = (20 mole × 6.022 × 10²³ molecules) ÷ 1 mol
X = 1.20 ×10²⁵ Molecules of H₂O
Answer:
The best practices officers should use when securing a crime scene is option D
D. They should secure a larger area than the actual crime scene
Explanation:
Officers should secure the scene by limiting access to the scene and movement within the scene
Three layers of secure perimeter should be used by officers to secure a crime scene, with the smallest inside perimeter being the actual crime scene
Next to the crime scene, is an inner perimeter which is the designated meeting point/command post
The outer perimeter, which is the third outer layer is to keep onlookers, passerby, and nonessential personnel at safety and out of the actual crime scene.
