Answer:
1.55×10²² molecules.
Explanation:
We'll begin by calculating the number of mole in 5.32 g of pure lead (Pb). This can be obtained as follow:
Mass of Pb = 5.32 g
Molar mass of Pb = 207 g/mol
Mole of Pb =?
Mole = mass /molar mass
Mole of Pb = 5.32/207
Mole of Pb = 0.0257 mole
Finally, we shall determine the number of molecules in 0.0257 mole of Pb. This can be obtained as follow:
From Avogadro's hypothesis,
I mole of Pb contains 6.02×10²³ molecules.
Therefore, 0.0257 mole will contain = 0.0257 × 6.02×10²³ = 1.55×10²² molecules.
Therefore, 5.32 g of pure lead (Pb) contains 1.55×10²² molecules.
Answer: it is a solid at room temperature.
Explanation:
The ions of the two reactants are Na{+} and Br{-}, so the formula of the product is NaBr.
and when the NaCl is a solid a room temperature. and when NaBr has similar properties to NaCl, so NaBr is a solid at room temperature too.
so our chemical formula for the product is NaBr and It's a solid at room temperature.
Answer:
Collid
Explanation:
Toothpaste is a colloid, because it's part solid and part liquid. ... A colloid is a heterogeneous mixture of two substances of different phases. Shaving cream and other foams are gas dispersed in liquid. Jello, toothpaste, and other gels are liquid dispersed in solid.
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.
